Posts Tagged ‘health’

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Caffeine had long been on the list of don’ts for people hoping to lead a healthy lifestyle. Doctors pointed to caffeine’s negative effects on the nervous system and its track record of increasing anxiety, stress and food cravings, as well as its damaging effects on sleep quality. Recent studies, however, suggest that coffee and caffeine may actually offer some significant medical benefits.

Remember the more than 19,000 studies mentioned earlier? Those studies have uncovered a range of positive effects that caffeine seems to have on the human body:

  • Regular coffee drinkers were 80 percent less likely to develop Parkinson’s disease.
  • Two cups a day reduced subjects’ risk for colon cancer by 20 percent.
  • Two cups a day caused an 80 percent drop in the odds of developing cirrhosis.
  • Two cups a day cut the risk of developing gallstones in half.

Studies have also suggested that caffeine is beneficial in treating asthma, stopping headaches, boosting mood and even preventing cavities


Some of these findings may have something to do with other healthful properties of the coffee bean, but most can be linked to caffeine directly. Researchers are even developing drugs for Parkinson’s disease containing caffeine derivatives.

More research is uncovering potential benefits from this commonly consumed drug. A study by the Byrd Alzheimer’s Institute in Tampa, Fla., showed that lab mice injected with caffeine were protected against developing Alzheimer’s disease. The injections even helped reduce symptoms in those that had the disease. The findings lead doctors to believe that up to five cups of coffee a day could have the same positive effect on humans

And a 2007 study at Rutgers University suggested that regular exercise combined with daily doses of caffeine could increase the destruction of precancerous skin cells in mice. Once again, the findings have not yet been tested on humans, but the indication is that it will have similar effects

Despite these recent findings, most doctors still recommend moderation in regard to caffeine intake. These studies give hope to those who stand by the value of their morning cup of Joe, but there’s still a long way to go to determine the long-term effects of caffeine use.

There is another side effect of caffeine: it raises the level of cortisol in your body. Read more here

by Chris Kresser (web)

grassfedbeefIn the first article of this series we talked about the negative impact of 4 common food toxins: wheat, industrial seed oil, fructose and processed soy. In the second article we discussed which fats, carbohydrates and proteins are the best source of fuel for your body. In this article we’re going to importance of eating real food.

“Real food” is:

  • Whole, unprocessed and unrefined
  • pasture-raised (a.k.a. grass-fed) and wild
  • local, seasonal and organic

Let’s look at each of these in turn.

Whole, processed and unrefined: if it comes in a bag or a box, don’t eat it!

The introduction of industrial food processing has without a doubt had the most detrimental effect on our health of any other factor in the last few hundred years – and possibly in the entire history of humankind.

Food refining has brought us all four of the food toxins destroying our health: white flour, white sugar & HFCS, industrial seed oils and processed soy products. It has also brought us chemical additives and preservatives, some with known negative effects and others with effects still unknown.

New research is revealing the harm these newfangled processed foods have on us almost every day. Just yesterday a study was published demonstrating that emulsifiers used in packaged foods ranging from mayonnaise to bread to ice cream increase intestinal permeability (“leaky gut”) and cause a chain reaction of inflammation and autoimmune disease.

Another study showed that diet soda consumption increases your risk of stroke and causes kidney damage, possibly because of the phosphoric acid used as an acidifying agent to give colas their tangy flavor.

To avoid the harm caused by processed and refined foods, a good general rule is “if it comes in a bag or a box, don’t eat it.

Of course not all foods that come in bags and boxes are harmful, so this isn’t meant to be taken literally. It’s just a helpful guideline. Butter is often packaged in a box, and Trader Joe’s (for some strange reason) packages vegetables in sealed plastic bags. That doesn’t mean you shouldn’t eat butter and vegetables.

But in general, if you follow this guideline, you’ll avoid most common food toxins. And that’s more than half the battle.

Pasture-raised animal products and wild-caught fish: as nature intended

While the reasons to eat pasture-raised animal products and wild-caught fish span social, political, economic and nutritional considerations, I’m only going to focus on nutritional factors here. For a more comprehensive discussion, check out Eat Wild.

Several studies have been done comparing the nutrient content of pasture-raised (PR) and grain-fed (confinement animal feeding operations, or CAFO) animal products. PR animal products are superior to CAFO in 2 primary respects: they have a better fatty acid profile, and higher levels of vitamins and other micronutrients.

Omega-6 ratio
If you remember from Step #1: Don’t Eat Toxins, for optimal health we want to consume a roughly equal amount of omega-6 (n-6) and omega-3 (n-6) fats. This ratio, referred to as the n-6 ratio, should be as close to 1 as possible. Studies have shown that grain-feeding animals depletes their omega-3 levels, thus raising the n-6:n-3 ratio. The following chart depicts the effect of grain-feeding on the omega-3 levels of cows:

https://i2.wp.com/eatwild.com/images/gr_nutrition2.gif

Ducket and colleagues studied the omega-3 and omega-6 content of both pasture-raised and grain-fed animal products. They found that grass-fed beef had an n-6 ratio of 1.65, whereas grain-finished beef was 4.84. They also found that grass-feeding decreased total fat content by 43%.

Rule and colleagues found an even more significant difference. They looked at the n-6 ratio of several different types of meat, ranging from pasture-raised bison and beef to wild elk to chicken. They found the following ratios:

  • Range-fed bison: 2.09
  • Feedlot bison: 7.22
  • Range-fed beef: 2.13
  • Feedlot beef: 6.28
  • Elk: 3.14
  • Chicken breast: 18.5

What is apparent from both Ducket and Rule’s studies is that pasture-raised beef has approximately three times the amount of omega-3 than grain-fed beef, and is much closer to the ideal n-6 ratio of 1. In fact, grass-fed beef has a superior n-6 ratio to even wild elk. This means that grass-fed beef falls within evolutionary norms for the fatty acid content of animals that humans have eaten throughout our history. Grain-fed beef does not.

Another interesting thing to note, which I mentioned in Step #2: Nourish Your Body, is the high n-6 ratio of chicken. In fact, it has about 14 times more n-6 than pasture-raised beef. This is why I recommend eating mostly beef, lamb and pork, and limiting chicken to the occasional meal (assuming you like it, that is). And when you do eat chicken, it’s best to choose skinless breast and cook it in a healthy traditional fat like butter or coconut oil, because the dark meat with skin has the highest concentration of n-6 fat.

Conjugated linoleic acid (CLA)
Meat, fat and dairy from pasture-raised animals are the richest source of another type of good fat, called conjugated linoleic acid (CLA).

CLA may have anti-cancer properties, even in very small amounts. In animal studies, CLA at less than one-tenth of one percent (0.1%) of total calories prevents tumor growth. In a Finnish study on humans, women who had the highest levels of CLA in their diet had a 60 percent lower risk of breast cancer than those with the lowest levels. In another human study, those with the highest levels of CLA in their tissues had a 50 percent lower risk of heart attack than those with the lowest levels.

Pasture-raised animal products are the richest known source of CLA in the diet, and are significantly higher in CLA than grain-fed animal products. When ruminant animals like cows and sheep are raised on fresh pasture alone, their products contain from 3-5 times more CLA than products from animals fed grain.

Minerals, vitamins and micronutrients
The Ducket study I mentioned above also found that pasture-raised animal products have much higher levels of several vitamins and minerals, including:

  • 288% greater vitamin E content
  • 54% greater beta-carotene content
  • Twice as much riboflavin (vitamin B2)
  • Three times as much thiamin (vitamin B1)
  • 30% more calcium
  • 5% more magnesium

Grass-fed products also have a lot more selenium than grain-fed products. Selenium plays an important role in thyroid function, has antioxidant effects and protects the body against mercury toxicity. Grass-fed bison has4 times more selenium than grain-fed bison.

Pasture-raised eggs
We see a similar difference between eggs from hens raised on pasture, and those raised in confinement. Pasture-raised hens contain as much as 10 times more omega-3 than eggs from factory hens. Pastured eggs arehigher in B12 and folate. They also have higher levels of fat-soluble antioxidants like vitamin E and a denser concentration of vitamin A.

Wild-caught fish

Farmed fish contain excess omega-6 compared to wild-caught fish. Tests conducted in 2005 show that wild-caught salmon contain 10 times more n-3 than n-6, whereas farmed salmon have less than 4 times the amount of n-3 than n-6.

Another study found that consuming standard farmed salmon, raised on diets high in n-6, raises blood levels of inflammatory chemicals linked to increased risk of cardiovascular disease, diabetes, Alzheimer’s and cancer.

Wild salmon also contains 4 times as much vitamin D than farmed salmon, which is especially important since up to 50% of Americans are deficient in this important vitamin.

Organic, local and seasonal: more nutrients, fewer chemicals

More nutrients
Organic plant foods contain, on average, 25 percent higher concentrations of 11 nutrients than their conventional counterparts. In particular, they tend to be higher in important polyphenols and antioxidants like vitamin C, vitamin E and quercetin.

Even more relevant in determining nutrient content is where your produce comes from, and in particular, how long it’s been out of the ground before you eat it. Most of the produce sold at large supermarket chains is grown hundreds – if not thousands – of miles away, in places like California, Florida and Mexico. This is especially true when you’re eating foods that are out of season in your local area (like a banana in mid-winter in New York).

A typical carrot, for example, has traveled 1,838 miles to reach your dinner table. Days – maybe more than a week – has passed since it was picked, packaged and trucked to the store, where it can sit on the shelves even longer.

The problem with this is that food starts to change as soon as it’s harvested and its nutrient content begins to deteriorate. Total vitamin C content of red peppers, tomatoes, apricots, peaches and papayas has been shown to be higher when these crops are picked ripe from the plant. This study compared the Vitamin C content of supermarket broccoli in May (in season) and supermarket broccoli in the Fall (shipped from another country). The result? The out-of-season broccoli had only half the vitamin C of the seasonal broccoli.

Without exposure to light (photosynthesis), many vegetables lose their nutrient value. If you buy vegetables from the supermarket that were picked a week ago, transported to the store in a dark truck, and then stored in the middle of a pile in the produce section, and then you put them in your dark refrigerator for several more days before eating them, chances are they’ve lost much of their nutrient value. A study at Penn State University found that spinach lost 47% of its folate after 8 days.

This is why buying your produce at local farmer’s markets, or even better, picking it from your backyard garden, are better options than buying conventional produce shipped from hundreds or thousands of miles away. Fruits and vegetables from local farms are usually stored within one or two days of picking, which means their nutrient content will be higher. And as anyone who’s eaten a fresh tomato right off the vine will tell you, local produce tastes so much better than conventional produce it might as well be considered a completely different food.

Fewer chemicals
Another important benefit of organic produce, of course, is that it’s grown without pesticides, herbicides and other harmful chemicals that have been shown to cause health problems – especially in vulnerable populations like children. A study published in the journal Pediatrics concluded that children exposed to organophosphate pesticides at levels typically found in conventional produce are more likely to develop attention deficit hyperactivity disorder (ADHD).

A panel of scientists convened by President Obama to study the effect of environmental toxins on cancer released a report in 2010 urging Americans to eat organic produce grown without pesticides, fertilizers or other chemicals. The report states that the U.S. government has grossly underestimated the number of cancers caused by environmental toxins.

The report especially highlights the risk of toxins in conventionally grown foods to unborn children. Exposure to harmful chemicals during this critical period can set a child up for lifelong endocrine disruption, hormone imbalances and other problems.

Supporting local economies and preserving resources
Aside from having more nutrients and fewer chemicals, there are other non-nutritional reasons to eat local produce. These were summarized well in Cornell University’s Northeast Regional Food Guide:

Community food systems promote more food-related enterprises in proximity to food production, marketing, and consumption. Such systems enhance agricultural diversity, strengthen local economies (including farm-based businesses), protect farmland, and increase the viability of farming as a livelihood. Local food systems mean less long-distance shipment of the produce we enjoy, which means decreased use of nonrenewable fossil fuels for food distribution, lower emission of resulting pollutants, and less wear on transcontinental highways.

I’ve also found that forming relationships with the people that grow my food leads to a greater sense of community and connection. In an increasingly technophilic, hyperactive world, that is especially welcome.

sprout

by Chris Kresser (web)

In step #1, we talked about what not to eat. In this article, we’ll talk about what to eat.

Most of the calories we get from food come from protein, carbohydrates and fat. These are referred to as macronutrients. We also get other important nutrients from food, such as vitamins and minerals. These don’t constitute a significant source of calories, so they’re called micronutrients.

For the last 50 years we’ve been told to follow a diet low in this or that macronutrient. From the 1950s up until the present day the American Heart Association and other similarly misguided and pharmaceutically-financed “consumer organizations” have advocated a low-fat diet. More recently, low-carbohydrate diets are all the rage.

Not all macronutrients are created equal

The problem with these approaches is that they ignore the fact that not all macronutrients are created equal. There’s a tremendous variation in how different fats and carbohydrates affect the body, and thus in their suitability for human consumption. Grouping them all together in a single category is shortsighted – to say the least.

What many advocates of low-fat or low-carbohydrate diets conveniently ignore is that there are entire groups of people around the world, both past and present, that defy their ideas of what constitutes a healthy diet.

For example, the low-fat crowd will tell you that eating too much fat – especially of the saturated variety – will make you fat and give you a heart attack. Tell that to the traditional Inuit, who get about 90% of calories from fat, and were almost entirely free of obesity and modern degenerative disease. The same is true for the Masai tribe in Africa, who get about 60-70% of calories from fat (almost entirely from meat, milk or blood.) And then there’s the modern French, who have the lowest rate of heart disease of any industrialized country in the world – despite the highest intake of saturated fat.

The low-carb crowd is very much aware of these statistics, which are often used in defense of low-carb diets as the best choice. Tell that to the Kitavans in Melanesia, who get about 70% of calories from carbohydrate and, like the Inuit and Masai, are almost entirely free of obesity, heart disease and other chronic, degenerative diseases that are so common in industrialized societies. We see a similar absence of modern diseases in the Kuna indians in Panama and the Okinawans of Japan, two other healthy indigenous populations that get about 65% of calories from carbohydrate.

These rather inconvenient exceptions to the low-fat and low-carb dogma vigorously promoted by advocates of both approaches show us that humans can in fact thrive on a wide range of macronutrient ratios, ranging from extremely high fat (Inuit, Masai) to very high carb (Kitavans, Kuna & Okinawans). They also hint at the idea that perhaps not all carbohydrates are the same in terms of their effects on human health.

Human fuel: food that nourishes the body

We need to shift away from the idea of macronutrients – as Dr. Kurt Harris of PaleoNu recently suggested – and move towards the idea of nourishment or fuel. This means we classify foods not based on their macronutrient ratios, but on their ability to provide the energy and nutrition the body needs to function optimally.

Gasoline and diesel are both fuel that cars can run on. If you put gasoline in a diesel engine, or vice versa, the engine may run but it won’t run well – or for very long. In a similar way, the human body can run on the entire range of fats, carbohydrates and proteins. But it runs much better on the ones it was designed to run on, and if you put too much of the others in, the body will eventually break down.

With this classification in mind, let’s look primarily at how the different types of fat and carbohydrate (our primary sources of energy) affect us, and which of them we should choose as our preferred “human fuel”.

Know your fats

LONG-CHAIN SATURATED FAT
We’ll begin with long-chain, saturated fats (LCSFA): myristic, palmitic and stearic acid. These fats are found mostly in the milk and meat of ruminant animals like cattle and sheep. They form the core structural fats in the body, comprising 75-80% of fatty acids in most cells, and they’re the primary storage form of energy for humans. In other words, when the body stores excess energy from food for later use, it stores it primarily as long-chain saturated fat.

Unlike polyunsaturated fats (PUFA) and carbohydrates like glucose and fructose, saturated fats have no known toxicity – even at very high doses – presuming insulin levels are in a normal range. Long-chain saturated fats are more easily burned as energy than PUFA. The process of converting saturated fat into energy the body can use leaves no toxic byproducts. In fact, it leaves nothing but carbon dioxide and water.

This means that, assuming you are metabolically healthy, you can eat as much saturated fat as you’d like without adverse consequences. I’m sure this will come as a surprise to many of you, since we’ve been collectively brainwashed for 50 years to believe that saturated fat makes us fat and causes heart disease. If you still believe this is true, watch these two videos and read all of the articles in my special report on cholesterol, fat and heart disease.

Verdict: eat as much as you’d like. The majority of the fats you consume should be LCSFA.

MEDIUM-CHAIN TRIGLYCERIDES
Medium-chain triglycerides (MCT) are another type of saturated fat. They’re found in coconut and in mother’s milk, and they have unusual properties. They’re metabolized differently than long-chain saturated fats; they don’t require bile acids for digestion and they pass directly to the liver via the portal vein. This makes MCTs a great source of easily digestible energy. They’re so easy to digest, in fact, that they’re used in the liquid hospital formulas fed to patients that have had sections of their intestine removed and aren’t able to digest solid food.

In addition to being a good energy source, MCTs have therapeutic properties. They’re high in lauric acid, a fat found in mother’s milk that has anti-bacterial, anti-viral and antioxidant properties.

Verdict: eat as much as you’d like. Coconut oil is an especially good cooking fat, because it is not vulnerable to the oxidative damage that occurs with high-heat cooking using other fats.

MONOUNSATURATED FAT
Monounsaturated fat (MFA), or oleic acid, is found primarily in beef, olive oil, avocados, lard and certain nuts like macadamias. Like saturated fats, MFA form the core structural fats of the body and are non-toxic even at high doses. Interestingly, monounsaturated fats seem to be the only fats that typically fat-phobic groups like the AHA and fat-friendly groups like Atkins and other low-carbers can agree are completely healthy.

Verdict: eat as much as you’d like. But be aware that certain foods that are high in monounsaturated fats, like nuts and avocados, can contain significant amounts of the dreaded omega-6 polyunsaturated fats, which we’ll discuss below. Exercise caution.

These three fats – long-chain saturated, medium chain triglycerides and monounsaturated – should form the bulk of your fat intake. In addition to their lack of toxicity, eating these fats will:

  • Reduce your risk of heart disease by raising your HDL, lowering your triglycerides and reducing levels of small, dense LDL (a type of LDL associated with a higher risk of heart disease). If you don’t believe me, read this.
  • Increase muscle mass. Muscle is composed of equal weights of fat and protein.
  • Stabilize your energy and mood. Fat provides a steadier supply of energy throughout the day than carbohydrate, which can cause fluctuations in blood sugar.

POLYUNSATURATED FAT: OMEGA-6 & OMEGA-3
Polyunsaturated fat (PUFA) can be subdivided into omega-6 and omega-3. PUFA are fragile and vulnerable to oxidative damage, a process that creates free radicals in the body and raises our risk for everything from heart disease to cancer. As I pointed out in Step #1: Don’t Eat Toxins, both anthropological and modern research suggest that for optimal health we should consume roughly the same amount of omega-6 and omega-3 fat (1:1 ratio), and that our total intake of PUFA should be no more than 4% of calories.

But Americans’ omega-6:omega-3 ratio today ranges from 10:1 to 20:1, with a ratio as high as 25:1 in some individuals! This means some people are eating as much as 25 times the recommended amount of omega-6 fat. And it is this excess consumption of omega-6 PUFA – not cholesterol and saturated fat – that is responsible for the modern epidemics of cardiovascular disease, type 2 diabetes, obesity, metabolic syndrome, autoimmune disease and more.

Omega-6 PUFA (linoleic acid, or LA) is found in small or moderate amounts of a wide variety of foods including fruits, vegetables, cereal grains and meat. But it is found in very large amounts in industrial processed and refined oils, like soybean, cottonseed, corn, safflower and sunflower. These oils are ubiquitous in the modern diet, present in everything from salad dressing to chips and crackers to restaurant food. LA is also relatively high in most nuts and in all poultry, especially in dark meat with skin.

Linoleic acid is an essential fatty acid. This means it is required for proper function but cannot be produced in the body, and thus must be obtained from the diet. However, the amount of omega-6 that is needed is exceedingly small: less than 0.5 percent of calories when supplied by most animal fats and less than 0.12 percent of calories when supplied by liver. When consumed in excess amounts – as is almost always the case in industrialized countries like the U.S. – omega-6 contributes to all of the diseases mentioned above.

Omega-3 PUFA can be further subdivided into short-chain (alpha-linolenic acid, or ALA) and long-chain (EPA & DHA). ALA is found in plant foods like walnut and flax, whereas EPA & DHA is found in seafood and to a lesser extent the meat and fat of ruminant animals.

While ALA is considered essential, the long-chain EPA & DHA are responsible for the benefits we get from eating omega-3 fats, and they form the denominator of the omega-6:omega-3 ratio. A common misconception is that we can meet our omega-3 needs by taking flax oil or eating plant foods containing ALA. It’s true that the body can convert some ALA to EPA & DHA. But that conversion is extremely inefficient in most people. On average, less than 0.5% of ALA gets converted into the long-chain EPA & DHA, and that number is even worse in people that are chronically ill or have nutrient deficiencies (common in vegans and vegetarians).

This means that it is probably EPA & DHA that are essential, in the sense that they are crucial for proper function but cannot be produced in adequate amounts in the body, and thus must be obtained from the diet. Of the two,evidence suggests that DHA plays the more important role.

Verdict: for optimal health, eat no more than 4% of calories (about 9g/d for a 2,000 calorie diet) of polyunsaturated fat, with an equal amount of omega-6 and omega-3. Make sure the omega-3 you eat is long-chain EPA & DHA (from seafood and animal sources) rather than short-chain ALA from plant sources like flax. It is very difficult to limit omega-6 to 4.5g/day. See this article for tips.

TRANS-FATS
There are two types of trans-fats: natural (NTF), and artificial (ATF). The primary natural trans-fat, conjugated linoleic acid (CLA) is found in small amounts (about 2%) in the meat, fat and dairy fat of ruminant animals. CLA does not have the harmful effects of ATFs, and may have anti-cancer properties and other benefits.

Artificial trans-fats have been linked with a variety of diseases. I think most people are aware of this, so I’m not going to belabor the point. We’ve still got carbs to talk about.

Verdict: avoid artificial trans-fats like the plague. Natural trans-fats like CLA are harmless and probably even beneficial, but as long as you’re eating long-chain saturated fats, you’ll get CLA. You don’t have to go out of your way to find it.

SUMMARY OF FATS
Long-chain saturated fat, monounsaturated fat and medium chain triglycerides should form the bulk of your fat intake. Long-chain omega-3 fats (EPA & DHA) should be consumed regularly, while omega-6 LA should be dramatically reduced. Click on the fat pyramid below for a graphic representation.

Know your carbs

Carbohydrates are broken down into either indigestible fiber, glucose or fructose. Let’s discuss the suitability of each of these as human fuel.

Glucose
Glucose is a simple sugar (monosaccharide) found mostly in plant foods like fruits, vegetables, starchy tubers and grains. It has three main uses in the body:

  • It forms structural molecules call glycoproteins;
  • Like fat, it is a source of energy for cells (especially in the brain); and,
  • it’s a precursor to compounds that play an important role in the immune system.

Glucose preceded fatty acids as a fuel source for living organisms by a very long time, and it is the building block of foods that have the longest evolutionary history of use by mammals like us. The fact that glucose can be produced in the body from protein is often used as an argument that we don’t need to eat it in the diet. But I agree with Dr. Harris’s interpretation that, rather than viewing this as evidence that that glucose isn’t important, we should view it as evidence that glucose is so metabolically essential that we evolved a mechanism to produce it even in its absence in the diet.

One of the few differences between our digestive tract and that of a true carnivore, like a lion, is that we produce an enzyme called amylase. Amylase allows us to digest starch – a long-chain polymer of glucose molecules we can’t absorb – into single molecules of glucose that easily pass through the gut wall into the bloodstream.

Presuming we are metabolically healthy, the glucose and starch we eat is digested and rapidly cleared by the liver and muscle cells. It is only when the metabolism is damaged – usually by years of eating toxins like refined cereal grains, industrial seed oils and fructose – that excess glucose is not properly cleared and leads to insulin resistance and diabetes.

Verdict: the range of glucose that is tolerated varies widely across populations and individuals. Assuming no metabolic problems and an active lifestyle, glucose may be consumed relatively freely. However, many people today do have some form of metabolic dysfunction, and live a sedentary lifestyle. If you fall into this category, glucose should probably be limited to 400 calories (about 100g) of glucose per day.

Fructose
Fructose is another simple sugar found primarily in fruits and vegetables. While it has the same chemical formula and caloric content as glucose, it has an entirely different effect on the body.

As I pointed out in Step #1: Don’t Eat Toxins, fructose is toxic at high doses. It damages proteins in a process called fructation, which disrupts metabolic function and causes inflammation and oxidative damage. To prevent this, fructose is shunted directly to the liver for conversion into glucose or innocuous fats. But this process damages the liver over time, leading to non-alcoholic fatty liver disease (which one in three Americans now suffer from) and metabolic syndrome.

Another issue is that excess fructose is not well absorbed in the gut, which in turn leads to its rapid fermentation by bacteria in the colon or abnormal overgrowth of bacteria in the small intestine. Small-bowel bacterial overgrowth, or SIBO, is now believed to be the major cause of irritable bowel syndrome (IBS), a common functional bowel disorder that is the second-leading cause of people missing work behind only the common cold.

Most people without metabolic dysfunction can handle small amounts of fructose (as found in a few servings of fruit per day) without problems. But on the scale that fructose is consumed in the U.S. – including 64 pounds of high-fructose corn syrup per person each year on average – fructose wreaks havoc on the body. It should therefore be limited as a source of carbohydrate.

Verdict: 3-4 servings a day of fruit is fine for people without metabolic problems. Those with fatty liver, insulin resistance or other issues should further limit fructose intake, and everyone should avoid high-fructose corn syrup and other concentrated sources like agave syrup.

Fiber
Fiber is plant matter that is indigestible to humans. But although we can’t digest it, some of the 100 trillion bacteria that live in our gut can. In fact, up to 10% of the body’s caloric needs can be met by the conversion of glucose into short-chain fats like butyrate, propionate and acetate by intestinal bacteria. These short-chain fats are the primary energy source for intestinal cells in the colon, and butyrate in particular has been associated with several benefits. These are outlined in The Perfect Health Diet, by Paul & Shou-Ching Jaminet. Butyrate:

  • Prevents obesity.
  • Heals the intestine.
  • Improves gut barrier integrity.
  • Relieves constipation.
  • Improves cardiovascular markers.
  • Reduces inflammation.
  • Stabilizes blood sugar.

The evidence clearly suggests that vegetable fiber is beneficial. However, just as not all fats are created equal, not all fiber is created equal. Grain fiber – which the AHA and other so-called “heart healthy” organizations have been promoting for decades – is toxic for two reasons: it contains toxic proteins like gluten, and it is prone to injure the intestinal wall.

We’ve been bullied into believing that grain fiber prevents heart disease and provides numerous health benefits. But this claim has only been tested in a single clinical trial, and the results were less than spectacular. The Diet and Reinfarction Trial, published in 1989, included 2,033 British men who had suffered a heart attack, and compared a high-fiber group with a control group. The high-fiber group ate whole grains and doubled their grain fiber intake from 9 to 17 grams per day.

How did that work out for them? Not too well. Deaths in the high fiber group were 22% higher over the two year study. 9.9% of the control group died vs. 12.1% of the high fiber group.

There are other reasons to limit all types of fiber. Fiber isn’t essential. Human breast milk doesn’t have any, and traditional people like the Masai – who are free of modern, degenerative disease – eat almost no fiber at all (subsisting on a diet of meat, blood and milk). And while fiber can feed the good bacteria in our gut and increase the production of beneficial short-chain fats like butyrate, it can also feed pathogenic and opportunistic bacteria in the gut.

Verdict: vegetable (but not grain) fiber is beneficial in moderate amounts – about one-half pound of vegetables per day. But think about vegetables and fiber as accompaniments or flavorful condiments to fat and protein, which should form the bulk of calories consumed, rather than the other way around.

SUMMARY OF CARBOHYDRATES
Assuming a healthy metabolism (which isn’t necessarily a safe assumption these days), glucose and starch can be eaten relatively freely, which fructose should be limited to 2-3 servings of fruit per day. Vegetable fiber is beneficial but should also be limited, to about one-half pound of vegetables per day. See the carb pyramid below for a graphic representation.

Pyramid containing carbs we should eat

Know your protein

What about protein? As it turns out, eating the right type of protein is easy if you simply follow Step #1 (don’t eat toxins) and base your diet on the healthy fats I listed above.

Protein is mostly found in animal products, seafood, nuts, legumes and grains. Legumes and grains have toxic compounds that can damage the gut. These toxins can be partially and in some cases completely neutralized by traditional preparation methods like soaking, sprouting and fermenting. But the vast majority of people in modern industrial societies don’t do this and aren’t willing to do it, so I generally recommend that people avoid them altogether.

As I explained above, nuts are often high in omega-6 LA, which we get far too much of as it is. So nuts should not constitute a significant source of protein. Walnuts are especially high. Just 100g of walnuts a day amounts to a whopping 266g of omega-6 per week. Keeping in mind that we want a 1:1 ratio of omega-6 to omega-3, you’d have to eat 34 pounds of salmon a week to achieve a balance. Good luck with that.

Poultry, especially dark meat with the skin on, can also be very high in omega-6 and should also be limited. For example, chicken skin has about 14 times more omega-6 than even grain-finished beef, and 10 times more than grain-finished pork.

That leaves the meat and milk (including butter, cream and cheese) of ruminant animals (beef & lamb), pork, and seafood as the most suitable sources of protein. Animal protein is easy to absorb, is not toxic and is rich in beneficial long-chain saturated fats and natural trans-fats like CLA. Seafood is similarly easy to absorb, and is the primary dietary source of long-chain omega-3 fats DHA & EPA, as well as micronutrients like vitamin D and selenium.

We don’t need a pyramid for protein; you can simply follow the fat pyramid and you’ll naturally get the right type and amount of protein.

9 Steps To Perfect Health

Posted: 31/08/2012 in Paleo Diet
Tags: , ,

by Chris Kresser (web)

man relaxing in the grassOur health continues to deteriorate at an alarming pace, and the incidence of chronic, degenerative disease is skyrocketing each year. Consider the following:

  • Diabesity (obesity + diabetes) affects more than one billion people worldwide, including 100 million Americans and 50% of Americans over 65.
  • More than half of Americans are overweight, and a full one-third are clinically obese.
  • Recent reports suggest that one-third of people born in 2010 will develop diabetes at some point in their lives.
  • 9 out of 10 Americans will develop high blood pressure before they die.
  • 4 out of 10 people who die each year in the U.S. die of heart disease, and rates of heart disease are projected to double in the next 50 years.
  • Rates of infertility are expected to double in the next decade.
  • According to the World Health Organization, depression is now the leading cause of disability, affecting more than 120 million people worldwide.

I could go on but I think you get the point. Our health is getting worse, not better.

Over the last 50 years the medical establishment has vigorously promoted a low-fat, high carbohydrate diet, claiming that it would protect us from heart disease and diabetes and make us healthier and happier. How has that worked out for us? The statistics above make it clear that the conventional approach has been a dismal failure that has not only failed to protect our health, but has directly contributed to the epidemic of modern disease.

All modern diseases share a similar cause

One of the most glaring mistakes conventional medicine makes is to assume that all of these modern diseases – diabetes, heart disease, depression, autoimmune disease, etc. – are unrelated conditions that don’t share a common cause. This is a convenient fiction created by the pharmaceutical industry (and perpetuated by the medical establishment) to sell more drugs.

The truth is that while these conditions do have unique features, they all share a common origin: the modern lifestyle. Poor diet, nutrient deficiencies, stress, lack of sleep, lack of or the wrong type of exercise, toxins and medications all directly contribute to the problems that are ruining our health.

The conventional approach is to treat each of these various problems with different drug, and ignore the fundamental factors that are at the root of all of them. That has been a stupendously unsuccessful approach. It’s time to replace it with a more holistic view of health, and to empower people to prevent and treat disease without unnecessary drugs or surgery.

by Chris Kresser (web)
masai
I was happy to see a new blog post by Kurt Harris over at PaleoNu yesterday. He’s one of my favorite bloggers, and he hasn’t written much over the last several months. Turns out he’s been boning up on evolutionary biology and paleoanthropology to determine what is currently knowable – and unknowable – about how our paleolithic ancestors lived and ate.

He has also been cultivating a relationship with a PaleoNu reader who happens to be a tutor in Zoology at an “institute of prominence” in the UK, with over 20 years of research and teaching in this field behind him. Preferring to remain anonymous, this fellow will be writing occasional guest articles under the pen name “Professor Gumby” (love it).

Paleo ambiguity

So what did Professor Gumby and Dr. Harris have to say in this first collaboration? In short:

  • It’s very difficult for us to know with any certainty what paleo people ate or how they lived.
  • The vast majority of studies of modern hunter-gatherers (HGs) have been ethnographic in nature, and as such are heavily influenced by the researchers own assumptions and objectives. This is a problem in all research, but it’s particularly notable in the anthropological literature.
  • Modern HGs are not analogous to paleolithic HGs. Even limited amounts of contact with modern people can have a profound impact on the diet and lifestyle of HG populations. This means we can’t simply study modern HG groups and assume that their habits reflect our distant ancestors.
  • Observer bias and influence are also issues with studies of modern HG populations. Professor Gumby (and others) have noted that the people they study will often change their dietary habits while being studied, perhaps to impress the researchers. In my family there’s a funny story about me when I was 8 years old eating a whole plate of spinach when a special guest came to visit for dinner one night. I hated spinach and wouldn’t touch it any other time. Turns out this phenomenon is common in anthropological field studies.
  • Along the same lines, modern HGs aren’t living in their traditional habitats. They’ve been displaced from their more optimal habitats by agriculturists and pastoralists. This means the diet they’re currently eating is probably atypical – “more akin to a ‘fall-back’ or ‘subsistence’ diet than an optimal one”, as Professor Gumby put it.

This last point is particularly salient. We can’t determine the optimal diet of a particular group of people simply by observing what they currently eat. As Dr. Harris points out:

It should be instructive to ask apparently healthy HGs what they prefer to eat in addition to what they have to eat. In a population that is healthy and not conditioned to a lifetime of non-foods as in the diet of a westerner with metabolic syndrome, it may have meaning to know what they prefer to eat. Not accounting for costs, how would they apportion their caloric intake from their extant food sources? I see no reason that relative food preferences could not be genetically or epigenetically influenced in addition to culturally influenced. Absent the interference of modern medicine, could a preference for the foods that make one live a healthier, more robust life be selected for and rapidly move through a population in a few generations? Do the Kitavans actually prefer yams/sweet potatoes/cassava over coconut and fish in the same ratio as the proportions they eat them in? Would Inuit happily prefer half their calories as sweet potatoes if they grew in the arctic? Or does each dietary pattern just reflect the preference to avoid starvation?

What we don’t know about paleo

The takeaway is simply this: it’s impossible to know for certain what our paleolithic ancestors ate by studying modern HG people. It’s difficult even to know what modern HG people eat when a bunch of researchers aren’t hanging around watching them.

There’s been a lot of discussion in the “paleo-sphere” about this lately. It comes up every time a fossil study is reported on, such as the most recent one that found starch on the teeth of Neaderthals, suggesting that they may have – gasp! – eaten grains on occasion. Of course these stories are pounced on by the anti-paleo set as evidence that grains have been a regular part of our diet for a long time and that proponents of the paleo diet don’t know what they’re talking about.

So on the one hand you’ve got paleo fundamentalists claiming to know exactly what paleolithic people ate, and stating with apparent certainty that grains and legumes were absolutely not included in their diets. Then you’ve got folks on the other end of the spectrum who claim that paleo is a just another “fad diet”, like the Zone or Atkins, with absolutely no basis in clinical or anthropological evidence.

They’re both wrong, of course.

It should be abundantly clear that we can’t know for certain what paleo people ate. They lived a long time ago, and we don’t have a time machine. Even if we did, and went back to study them, they’d probably pull the equivalent of me eating spinach when that special guest visited.

But this doesn’t mean we simply disregard what we do know about our paleolithic ancestors and modern HGs, nor does it mean that we can’t extrapolate that knowledge into helpful guidelines for what a species-appropriate diet might be for us humans.

What we do know about paleo

We still know, for example, that modern diseases like diabetes, obesity, cancer, autoimmunity and heart disease were rare (or even nonexistent) in paleo people and are still rare in the few HG groups around the world that have been lucky enough to preserve their traditional diet and lifestyle.

We also know that when modern foods like wheat flour, industrial seed oils and sugar are introduced in these populations, the incidence of modern diseases goes up commensurately. And, even more telling, when these groups return to their traditional ways, the modern diseases disappear again. This suggests that it wasn’t some genetic vulnerability that caused them to develop modern diseases with the introduction of modern foods.

So yes, paleo may not actually be paleo. We will probably never know exactly what our paleo relatives ate.

My response to that? I couldn’t care less.

Why? Because we know enough about ancestral diets in a general sense to suggest that they are superior to modern diets for human health. And we know enough – thanks to current clinical research – about modern foods like flour, seed oils and sugar to know that we shouldn’t be eating them.

That’s enough for me.

I really wish there was a word (other than paleo) I could use to describe a nutrient-dense, toxin-free, whole-foods based diet. Because that’s kind of a mouthful, and it leaves a lot open to interpretation. A raw-food vegan could hear me say that and think I’m talking about their diet. I’m not.

So I go on using the term “paleo” to loosely refer to a diet that emphasizes animal protein and fats, starchy & non-starchy vegetables, fermented foods, raw dairy (when tolerated) and fruit, nuts & seeds (in moderation).

I wish there was another term I could use that didn’t evoke a quasi-religious debate. But I don’t know of one, so for now, I guess I’ll just have to deal with all of the baggage that comes with “paleo”.