Is The Paleo Diet Healthy?

Written by Dr. Steve Chaney on . Posted in Paleo Diet

Did Cave Men Have The Secret For A Longer, Healthier Life?

Author: Dr. Stephen Chaney

 

the paleo dietIt seems like everyone you talk to is following the Paleo diet or knows someone who is following the Paleo diet. It is the latest diet fad. But, is the Paleo diet healthy?

If you have been around for a few years, like me, you have seen lots of fad diets come and go. They are immensely popular for a few years. Then people discover their weight loss was temporary or they aren’t any healthier, and the diet slowly fades into obscurity.

Is the Paleo diet one of those fad diets that will fade into obscurity, or is it a healthy diet that will stand the test of time? A lot has been written about the Paleo diet, both pro and con. I have analyzed the science behind the claims and counter-claims so I can bring you the truth about the Paleo diet.

 

Unicorns And the Paleo Diet

 

the paleo diet and unicornsI titled this section “Unicorns and the Paleo Diet” because both are myths. In fact, the Paleo Diet is based on several myths.

Myth #1: Our ancestors all had the same diet. What we currently know as the Paleo diet is based on the diets of a few primitive hunter-gatherer societies that still exist in some regions of the world. However, when you look at the data more carefully, you discover that the diet of primitive societies varies with their local ecosystems.

The “Paleo diet” is typical of ecosystems in which game is plentiful and fruits and vegetables are less abundant or are seasonal. In ecosystems where fruits and vegetables are abundant, primitive societies tend to be more gatherers than hunters. They eat more fruits and vegetables and less meat.

The assumption that starchy foods were absent in the paleolithic diet is also a myth. For some primitive societies, starchy fruits or starchy roots are a big part of their diet. In short, our paleolithic ancestors ate whatever nature provided.

Myth #2: Our genetic makeup is hardwired around the “paleolithic diet.” In fact, humans are very adaptable. We are designed to thrive in a wide variety of ecosystems. It is this adaptability that has allowed us to expand to every nook and cranny of the world.

For example, the enzymes needed to digest grains are all inducible, which means the body can turn them on when needed. Our paleolithic ancestors may not have eaten much grain, but we can very quickly adapt to the introduction of grains into our diet.

Myth #3: Our paleolithic ancestors were healthier than modern man: It many respects, the paleolithic diet is healthy, as I will discuss below. However, we need to remember that our paleolithic ancestors rarely lived past 30 or 40. They simply did not live long enough to experience degenerative diseases like heart disease and cancer. We have no idea whether a diet that served our paleolithic ancestors well will keep us healthy into our 70s, 80s and beyond.

However, just because the Paleo diet is based on mythology does not mean that it isn’t healthy. Let’s look at the pros and cons of the Paleo diet.

 

The Pros Of The Paleo Diet

 

the paleo diet thumbs upThere are lots of things to like about the Paleo diet. For example:

  • It eliminates sodas, fast foods, processed foods, sugar and salt. Any diet that does that is a vast improvement over the typical American diet.
  • It emphasizes fresh fruits and vegetables, another big improvement over the typical American diet.
  • It has a healthier profile of fats than the other low carb diets. It favors grass-fed beef, wild-caught fish, and free-range chicken, so it has less saturated fat and more omega-3s. It also emphasizes healthy oils such as olive, walnut, avocado, and flaxseed. In this regard, it is clearly healthier than the other low carb diets. It does include coconut oil, which is a concern. As I have pointed out in a previous article, Is Coconut Oil Bad For You, there is no convincing evidence that coconut oil is healthy.
  • It emphasizes use of unrefined or extra virgin oils rather than refined oils. That is a plus for most oils because the unrefined oils are more likely to contain antioxidants and beneficial phytonutrients. It is, however, a concern for coconut oil because the unrefined oil is more likely to contain cancer-causing aflatoxins.
  • Like most other restrictive diets that eliminate processed foods, it can give short term weight loss, although long term weight loss is less certain.

 

The Cons Of The Paleo Diet

the paleo diet thumbs down

There are, however, some concerns about the Paleo diet. Other experts have commented on the cost and difficulty in following the diet, especially if you eat out a lot, so I won’t comment on those aspects here. I will stick with nutritional concerns with the Paleo diet. For example:

  • It eliminates cereal grains, legumes, and dairy. I am always concerned with the nutritional adequacy of diets that eliminate whole food groups. For example:
    • Dairy is a major source of calcium and vitamin D in the American diet. Eliminating dairy has the potential to increase the risk of osteoporosis.
    • Whole grains, legumes and dairy are important sources of magnesium. Magnesium deficiency has the potential to increase the risk of heart disease, among other things.
    • Most Americans are already not getting enough of these nutrients in their diet. We can scarcely afford to eliminate foods that are good sources of these nutrients.
    • It is possible to carefully design a Paleo diet so these nutrients are provided by other foods, but most people don’t carefully design their daily diet.
  • It recommends increasing protein intake to 19 – 35% of calories. Because legumes have been eliminated, the increased protein intake is coming almost entirely from animal protein, primarily red meat and fish. I will discuss the health concerns with red meat below. However, there is a practical consideration as well. Grass-fed beef is not always available, especially if you eat out frequently. If you are not eating grass-fed beef, you will be taking in more saturated fats and the healthier fat profile of the Paleo diet will disappear.
  • It has been influenced by the recent hype about health benefits of coconut oil. Coconut oil is just one of several oils that are recommended. However, if you look on the internet today, coconut oil is featured in almost every Paleo diet recipe. Until we have definitive evidence whether or not coconut oil is healthy, I would emphasize the other oils recommended for the Paleo diet, and use coconut oil sparingly.
  • There are no studies showing the Paleo diet is healthy long term. In contrast, there are long term studies showing that Vegan, Mediterranean, and DASH diets decrease the risk of heart disease, diabetes, some cancers and Alzheimer’s.

 

Concerns About Red Meat

the paleo diet red meatThe International Agency For Research On Cancer (IARC), the agency created by the WHO to set international standards for cancer risk, has designated red meat as a class 2a carcinogen. That designation means that there is probable cause to believe that it increases cancer risk in humans. The evidence is best for increased risk of colon cancer and breast cancer, although there is some evidence that it may increase risk of pancreatic and prostate cancer.

The increased cancer risk of red meat does not seem to be due to its fat content, so grass fed beef is just as likely to increase cancer risk as conventionally produced beef. There are multiple proposed mechanisms for this effect:

  • When fat and juices from the meat drip onto an open flame, carcinogenic polyaromatic hydrocarbons are formed that stick to the surface of the meat. This can be reduced, but not eliminated, by lower fat meat choices.
  • When red meats are cooked at high temperatures, amino acids in the meat combine with a compound called creatine, which is found in all red meats, to form carcinogenic heterocyclic amines. This can be reduced by cooking the meat at lower temperatures.
  • Heme iron, which is found in all red meats, combines with other component of our diet to form carcinogenic N-nitroso compounds in our intestines.
  • People who eat high meat diets have an entirely different population of intestinal bacteria than people who eat no meat. Several recent studies suggest that the intestinal bacteria of meat eaters are more likely to convert the foods we eat into chemicals that increase the risk of cancer and heart disease.

To be clear, red meat is a probable carcinogen and we aren’t sure of the exact mechanism(s) that cause this carcinogenicity. We do not yet have definitive evidence that red meat causes cancer. However, there is good reason to be cautious about how much red meat we consume.

The good news is that the antioxidants, fiber and phytonutrients found in fruits and vegetables can block most of these cancer-causing pathways. That means that small amounts of red meat in a largely plant-based diet may not be as concerning. Specifically, an ounce of red meat in a large green salad or stir fry is much less likely to increase your cancer risk than a 6 ounce steak.

Is The Paleo Diet Healthy?

 

As mentioned above, there is a lot to like about the Paleo diet. It is healthier than the typical American diet, and it is healthier than most of the low carb diets. I have concerns about the nutrition adequacy of any diet that eliminates whole food groups and the heavy emphasis on red meat. There is also no proof that the Paleo diet is healthy long term.

Since the restrictions of the Paleo diet are based on mythology rather than science, my recommendation would be to loosen the restrictions on whole grains, legumes & low-fat dairy, and rely less on red meat as a protein source. If you did that, the diet would more closely resemble the Mediterranean and DASH diets, which we know are healthy long term.

 

The Bottom Line

 

  1. The Paleo diet is based on a myth.
    • Our paleolithic ancestors did not eat a single diet. They followed a variety of diets depending on the foods most available where they lived.
    • Our bodies are not genetically hardwired for a single diet, but are designed to adapt to a wide variety of foods. For example, all of us have the enzymes needed to digest grains, and those enzymes are inducible.
    • We don’t know whether the paleolithic diet is healthy. The average lifespan of our paleolithic ancestors was in the range of 30 to 40 years. We have no idea whether a diet that served our paleolithic ancestors well will keep us healthy into our 70s, 80s and beyond.
  2. However, the fact that the Paleo diet is based on a myth does not make it unhealthy. In fact, there is a lot to like about the Paleo diet.
    • It eliminates sodas, fast foods, processed foods, sugar and salt which makes it much healthier than the standard American diet.
    • It emphasizes fresh fruits and vegetables, which is also an improvement over the standard American diet.
    • If features a relatively healthy profile of fats, which makes it healthier than most other low carb diets.
    • It favors unrefined or extra virgin oils, which are generally healthier than highly processed oils. The exception is coconut oil because unrefined coconut oil may be contaminated with aflatoxins.
    • It can give short term weight loss, although long term weight loss is uncertain.
  3. However, there are concerns about the long-term safety of the Paleo diet. The minor concerns are:
    • The elimination of whole grains, legumes, and dairy from the diet creates the potential for nutritional deficiencies that can have long-term health consequences. It is possible to carefully design a Paleo diet so these nutrients are provided by other foods, but most people don’t carefully design their daily diet.
    • Most of the recipes you find on the internet for the Paleo diet use coconut oil. This is a concern because we don’t know whether coconut oil is healthy. My recommendation would be to substitute the healthier oils that are also part of the Paleo diet.
  4. More serious concerns are:
    • The heavy reliance on red meat. Red meat is classified as a probable carcinogen, potentially increasing the risk of colon cancer, breast cancer, pancreatic cancer and prostate cancer. The potential carcinogenicity of red meat is not reduced by substituting grass-fed beef for conventionally produced beef.
    • There are no clinical studies showing the Paleo diet is healthy long term. In contrast, there are long term studies showing that Vegan, Mediterranean, and DASH diets decrease the risk of heart disease, diabetes, some cancers and Alzheimer’s.
  5. Because the restrictions of the Paleo diet are based on myth rather than science, there are simple work arounds for the concerns. If one were to loosen the restrictions on whole grains, legumes and low-fat dairy & reduce the reliance on red meat, you would have a diet closer to the Mediterranean and DASH diets, which we know are healthy long term.
  6. For details, read the article above.

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

 

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Should You Avoid Sugar Completely?

Posted October 24, 2017 by Dr. Steve Chaney

Is It The Sugar, Or Is It The Food?

Author: Dr. Stephen Chaney

 

Should we avoid sugar completely?  Almost every expert agrees that Americans should cut down on the amount of sugar we are consuming. However, for some people this has become a “sugar phobia”. They have sworn that “sugar shall never touch their lips”. Not only do they avoid sugar sweetened sodas and junk food, but they also have become avid label readers. They scour the label of every food they see and reject foods they find any form of sugar listed as an ingredient. Is this degree of sugar avoidance justified?

 

Should We Avoid Sugar to Keep it From Killing Us?

 

Let me add some perspective:

  • If you just take studies about the dangers of sugar at face value, sugar does, indeed, look dangerous. Excess sugar consumption is associated with increased risk of obesity, diabetes, and heart disease. However, when you look a little closer, you find that most of these studies have been done by looking at the correlation of each of these conditions with sugar sweetened beverage consumption (sodas and fruit juices).

A few studies have looked at the correlation of obesity and disease with total “added sugar” consumption. However, 71.6% of added sugar in the American diet comes from sugar sweetened beverages and junk food. None of the studies have looked at the sugar from healthy foods like fruits, vegetables, and whole grains. That’s because there is ample evidence that these foods decrease the risk of obesity, diabetes, and heart disease.

  • For example, if apples had a nutrition label, it would list 16 grams of sugar in a medium 80 calorie apple, which corresponds to about 80% of the calories in that apple. The sugar in an apple is about the same proportion of fructose and glucose found in high fructose corn syrup. Apples are not unique. The nutrition label would read about the same on most other fruits. Does that mean you should avoid sugar from all fruits? I think not.

Avoid Sugar or Avoid Certain Foods

 

avoid sugar from junk foodsThe obvious question is: “Why are the same sugars, in about the same amounts, unhealthy in sodas and healthy in fruits?” Let’s go back to those studies I just mentioned—the ones that are often used to vilify sugars. They are all association studies, the association of sugar intake with obesity and various diseases.

The weakness of association studies is the association could be with something else that is tightly correlated with the variable (sugar intake) that you are measuring. Could it be the food that is the problem, not the sugar?

If we look at healthy foods (fruits, vegetables, whole grains) they are chock full of vitamins, minerals, phytonutrients, fiber, and (sometimes) protein. Fiber and protein slow the absorption of sugar into the bloodstream. As a result, blood sugar levels rise slowly and are sustained at relatively low levels for a substantial period of time.

In sodas there is nothing to slow the absorption of blood sugar. You get rapid rise in blood sugar followed by an equally rapid fall. The same is true of junk foods consisting primarily of sugar, refined flour and/or fat.  Avoid sugar from those types of foods.

Another consideration is something called caloric density. Here is a simple analogy. I used to explain the concept of caloric density to medical students in my teaching days. There are about the same number of calories in a 2-ounce candy bar and a pound of apples (around 278 in the 2-ounce candy bar and 237 in a pound of apples). You can eat a 2-ounce candy bar and still be hungry. If you eat a pound of apples you are done for a while. In this example, the 2-ounce candy bar had a high caloric density (a lot of calories in a small package). Perhaps a more familiar terminology would be the candy bar was just empty calories.

Are Sodas and Junk Foods Killing Us?

avoid sugar from candyPutting all that together, you can start to understand why the foods the sugars are in are more important than the sugars themselves. When you consume sugars in the form of sugar sweetened beverages or sugary junk foods, your appetite increases. We don’t know for sure whether it is the intense sweetness of those foods, the rapid increase and fall in blood sugar, or the high caloric density (lots of calories ina small package) that makes us hungrier. It doesn’t matter. We crave more food, and it isn’t usually fruits, vegetables, and complex carbohydrates we crave. It’s more junk. That sets in motion a predictable sequence of events.

  • We overeat. Those excess calories are stored as fat and we become obese. [Note: The low carb enthusiasts will tell you our fat stores come from carbohydrates alone. That is incorrect. All excess calories, whether from protein, fat, or carbohydrate, are stored as fat.]
  • It’s not just the fat you can see (belly fat) that is the problem. Some of that fat builds up in our liver and muscles. This sets up an unfortunate sequence of metabolic events.
  • The fat stores release inflammatory cytokines into our bloodstream. That causes inflammation. Inflammation increases the risk of many diseases including heart disease and cancer.
  • The fat stores also cause our cells to become resistant to insulin. That reduces the ability of our cells to take up glucose, which leads to hyperglycemia and type 2 diabetes. [Note: The low carb enthusiasts will tell you carbohydrates cause type 2 diabetes. That is also incorrect. It is our fat stores that cause insulin resistance and type 2 diabetes. Our fat stores come from all excess calories, not just excess calories from carbohydrates.]
  • Insulin resistance also causes the liver to overproduce cholesterol and triglycerides and pump them into the bloodstream. That increases the risk of heart disease.
  • Sugar sweetened beverages and sugary junk foods also displace healthier foods from our diet. That leads to potential nutrient shortfalls that can increase our risk of many diseases.

However, none of this has to happen. The one thing that every successful diet has in common is the elimination of sodas, junk foods, fast foods and convenience foods. You should avoid sugar from those foods as much as possible. Once you eliminate those from your diet,you significantly enhance your chances of being at a healthy weight and being healthy long term.

 

What About Protein Supplements And Similar Foods?

Of course, the dilemma is what you, as an intrepid label reader, should do about protein supplements, meal replacement bars, or snack bars. They are supposed to be healthy, but the label lists one or more sugars. Even worse, the sugar content is higher than your favorite health guru recommends.  So, should you avoid sugar from supplements and the like?

In this case, a more useful concept is glycemic index, which is a measure of the effect of the food on your blood sugar levels. Healthy foods like apples may have a high sugar content, but they havea low glycemic index.

avoid sugar and consume protein to slow absorbptionThe same is true for the protein supplements and bars you are considering. Rather than looking at the sugar content, you should be looking for the term “low glycemic” on the label. That means there is enough fiber and protein in the food to slow the absorption of sugar into the bloodstream and stabilize your blood sugar levels.

What Does This Mean For You?

Don’t misunderstand me. I am not advocating for unlimited consumption of sugar. We should work on ways to avoid sugar or reduce the amount of sugar in our diet. On the other hand, we don’t need to become so strict that we and our family need to eat foods that taste like cardboard. We also don’t want to replace natural sugars with artificial sweeteners. I have warned about the dangers of artificial sweeteners previously.

We can go a long way towards reducing sugar by just eliminating sodas, other sugar sweetened beverages, junk foods, fast foods, convenience foods, and pastries from our diet. When considering fast foods and convenience foods, we should check the label for hidden sugar. For example, some Starbucks drinks are mostly sugar. When considering foods that are supposed to be healthy, we should look for the term “low glycemic” on the label.

So we don’t have to avoid sugar completely, but we should reduce sugar from sugar sweetened beverages and junk food.

 

The Bottom Line

 

We need to keep warnings about the dangers of sugar in perspective:

  • The studies showing that sugar consumption leads to obesity, diabetes, and heart disease have all been done with sodas and junk foods.
  • Many fruits have just as much sugar as a soda. They also contain about the same proportion of fructose and glucose as high fructose corn syrup. Yet we know fruits are good for us.
  • Diets rich in fruits, vegetables and whole grains decrease our risk of obesity, diabetes, and heart disease.
  • That is because the sugar in whole foods is generally present along with fiber and protein, which slows the absorption of sugar and prevents the blood sugar spikes we get with sodas and junk foods.
  • In the case of prepared foods like protein supplements, you should look for “low glycemic” on the label rather than sugar content. Low glycemic means that there is enough fiber and protein in the product to slow the absorption of sugar and prevent blood sugar spikes.
  • Don’t misunderstand me. I am not advocating for unlimited consumption of sugar. We should all work on ways to avoid sugar from junk foods or to reduce the amount of sugar in our diet. On the other hand, we don’t need to become so strict that we and our family need to eat foods that taste like cardboard. We also don’t want to replace natural sugars with artificial sweeteners.
  • We can go a long way towards reducing sugar by just eliminating sodas, other sugar sweetened beverages, junk foods, fast foods, convenience foods, and pastries from our diet. When considering fast foods and convenience foods, we should check the label for hidden sugar. When considering foods that are supposed to be healthy, we should look for the term “low glycemic” on the label.

For more details, read the article above.

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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