Unless you've been living under a rock the past ten years you have heard about the paleo or ancestral diet. The basic premise is that humans evolved eating a certain diet composed of foods that could be hunted or gathered. Our diet, as a species, has changed dramatically over the last 10,000 years and it is argued that our genes have not had time to catch up to many of those changes. This, it is said, is where modern diseases of civilization have begun and by reverting to a "paleo" diet, many can be prevented or corrected. The paleolithic diet is composed of real foods such as meat, vegetables, fruit, and depending on the subsection, sometimes seeds/nuts, starchy tubers/roots, and honey. Basically, if you could go out and kill it or find it you can and should eat it. Conversely, things that could not be found or hunted should not be eaten, especially things like grains, which are cultivated, and dairy, which deals with the domestication of animals. Both of which are argued to be relatively recent phenomena and therefore humans have not fully adapted to dealing with them. The problem with this kind of thinking is the assumption that anything paleolithic man ate is inherently healthy and that anything paleolithic man didn't eat is inherently unhealthy. This, in my opinion, is faulty logic. There are some aspects of that thinking that work, like grains being potentially problematic for some people, as well as beans/legumes, but then to say that all dairy, regardless of form is unhealthy and/or harmful, as well as something like roots/tubers just because they may not have been a paleolithic staple. In my opinion when discussing what one should or should not eat it depends on a myriad of factors. What stage of life are you in? What is your current state of health? Are you afflicted with a particular condition or disease? What is the current state of your gastrointestinal microbiome and GI tract in general? What are your goals? Are you interested in weight loss, building muscle, or fueling activity? These are but a few of the questions that should be asked before you consider what diet or foods are best for you. That being said, I think paleo-type eating is a good starting point for most people, especially overweight and/or sedentary people looking to improve their baseline health and energy levels. The rest of the post is going to be devoted to what paleo-style diets advocate and the positives and negatives associated, as well as some of the things they leave out, and a few other factors that don't often get considered. As always, this post will be longer than I intended.
Paleo principles:
- eat meat; preferably pasture raised or wild and lean (not all paleo factions agree about the latter)
- eat some fruit, but not too much
- eat lots of green, leafy vegetables
- eat nuts, seeds, and fat containing fruits (olives, avocados, coconut, etc.)
- eat eggs preferably pasture raised
- eat seafood like salmon, mackerel, and tuna for the omega-3's
- avoid grains in all forms including the "ancient" grains like quinoa, amaranth, teff, kamut, etc.
- avoid starchy tubers like potatoes and sweet potatoes* (not all paleo factions agree here)
- avoid dairy in all forms
- avoid beans and legumes in all forms
- don't eat processed food
- get plenty of sunshine
- get plenty of sleep
- drink enough water
Focusing a lot of attention on eating enough pasture raised or wild game is a good thing. Animal flesh is rich in protein, vitamins, minerals, the right kinds of fats for human health, and is damn tasty. Eating factory farmed meat is not much different than eating the foods (corn and soybeans) that they are fed. Paleo advocates often times miss the fact that when an animal was killed, in paleolithic times, that the entire animal was consumed. This means not only the fat, but also the organs, marrow, and brain. The fat is a great energy source and mostly of the saturated and monounsaturated variety, the healthy kind, with very little polyunsaturated fat (the not so good kind which I'll discuss more later or in another post) and when you're potentially going long periods of time without eating, fat is a very dense source of calories. Not such a problem in today's society but that doesn't mean fatty cuts of meat should be shunned. In fact, just the opposite is true. Fatty cuts of meat should be sought out. As an added bonus, these are often the most economical in value. Next up is the lack of focus on organ meats. Not only is this where most of the minerals and vitamins are stored but they all fit the "lean" recommendation, besides the brain tissue. Organ meats are an acquired taste for most but when mixed with muscle meat and spiced properly they are very palatable and only need to be consumed about once per week. Liver is probably the densest and most important source of nutrition but the heart, kidneys, and brains are all good sources as well.
Today's fruit is much different than it was even two or three generations ago as we have bred it to contain more sugar per unit volume which dilutes the nutrient content and increases the caloric load. Soils are also less nutrient rich due to over farming and mono-culture practices. That being said, fruit is still low in toxins (important to remember for later), can contain a hefty dose of antioxidants, and is a good source of sugar and calories because after all, we have to eat something. Plus, the more active a person is and the better his or her body composition (muscle to fat ratio), the better he or she is able to handle sugar and carbohydrates. Fruit then, should probably be looked at as a conditional food. The fatter you are the less fruit you eat, to a point, and the less active you are the less fruit you eat, again, to a point. There is a time and a place for eating less carbohydrates, but not all the time, as that can lead to negative repercussions, which I'll discuss in a later post.
If you don't eat your green vegetables its impossible to be healthy right? Not so fast, unlike animals who have fast moving legs or big teeth to deal with their predators, plants aren't so lucky. Plants then, have developed an arsenal of internal defense systems to discourage being eaten, because if they're eaten they don't reproduce and ultimately die out. So, these defense systems can be protection against the sun like the pigments in tomatoes and blueberries, which turn out to be beneficial for human health, or they can be developed to resist predation by mammals and/or insects, which are sometimes downright harmful to human health. The main compounds we will concern ourselves with are the lectins, of which gluten is one, technically a prolamine, the agglutinins, like wheat germ agglutinin, the nutrient binders, like phytates and oxalates, as well as the enzyme inhibitors. The lectins (present in seed grains, nuts, seeds, legumes, and some fruits and vegetables) mainly target the gut and irritate the mucosal lining, punch holes in the gastrointestinal cells, or increase the permeability of the gut through activation of our intrinsic proteins. All of this means that stuff (like proteins and bacteria) that should remain inside the gut end up leaking into the bloodstream where they can cause problems like low grade inflammation and food sensitivities. Agglutinins, like wheat germ agglutinin (WGA), have some pretty nasty effects on the body as well, like activating immune cells to produce inflammatory compounds, binding to the insulin receptor making fat loss more difficult, interfering with the leptin receptor in the brain, which throws off nutrient signaling (makes you eat more or feel like you didn't eat enough), and even prevents cells from producing the vitamin D receptor so despite your supplementation or sun exposure your cells may not actually be taking up the vitamin D. Interestingly enough, its the whole grains with the bran intact that contain the most agglutinin. The nutrient binders like phytates or oxalates are responsible for sequestering the minerals present in the plant and thus make their nutrient unavailable for absorption and can also bind free minerals ingested with said plant material. Uncooked vegetables have much more of these compounds, so cooking the plants first is the best choice here. Lastly, are the protease inhibitors present in plant foods which prevent the digestion of the plant and harm the animal (by preventing protein digestion), which at best makes the plant matter less nutritious and at worst increases the consumer's need for protein. All that being said, some plants have less of these defense systems than others, ironically its the pesicide/insecticide sprayed ones, and plants still contain vitamins and minerals which are rendered more bioavailable upon cooking. Am I saying not to eat vegetables? No. What I am saying is that there probably is too much of a good thing and some reasons to eat very little of them. I think you can be perfectly healthy without eating much green plant matter at all. If you choose to eat it, fine, just know there are risks, some which I haven't mentioned like thyroid suppression and damaging DNA, but there are also beneficial compounds in these plants as well, so its really a mixed bag. The best advice would be to eat a variety and focus most of your efforts on the low toxin foods.
A lot of the issue with consuming a large quantity of nuts and seeds has already been discussed, like the lectins, nutrient binders and the protease inhibitors, but nuts/seeds present another problem; potentially bigger and more important than the grains issue. Nuts and seeds contain, by percentage, the most polyunsaturated fats (PUFA) of any food group. We have been told that polyunsaturated fats lower our cholesterol, are heart healthy, and should make up a good proportion of our fat calories. We are told that omega 6's are more inflammatory, but still essential, and that omega 3's are anti-inflammatory, and of course, essential. There is a good bit of research that refutes the essential nature of both kinds of fats, but that is the subject of another article. The real problem with the large amount of PUFA contained within nuts and seeds (including seed grains like corn and wheat) is that due to the multiple number of double bonds contained within the fat they are susceptible to oxidation and damage. Two things in particular are capable of causing this damage to the fats. Heat and oxygen. Two things abundant within the human body. Once these fats are damaged they become lipid peroxides (free radicals) that participate in reactions that damage cell membranes, DNA, and cause inflammation. Research shows that diets containing more than 3% of calories from PUFA increase cancer risk by about 40%. The damage they cause is most directly harmful to the liver, blood vessel walls, and the gut wall. I will delve into this topic to a greater degree in future posts but all of these effects are pretty bad and correlate rather well with the increasing incidence of vascular disease and bowel disease since they became a dietary staple in Western society. Fat from fruit like olives, avocado, and coconut are much healthier, contain far less PUFA, and in the case of coconut, contain a very special kind of saturated fat that plays very well with carbohydrates and has many beneficial effects on the body. More on this in future posts.
Not much to say about eggs. They are pretty awesome, especially the yolks. As always, pasture raised is best. Some people with gut issues can have a reaction to the egg white proteins and some people with no gut issues to speak of can develop a problem if they are consumed too often due to a compound present in the white (lysozyme). Eat eggs, just not everyday, well, unless its the yolk. Then, go nuts (figuratively).
Seafood is a great source of protein, vitamins, and trace minerals like iodine. That being said, fish that contains large amounts of omega 3's can be problematic, as it is a PUFA, and a more highly unsaturated PUFA to boot, can suppress the immune system, and cause liver damage if ingested with fructose or alcohol. I don't really want to get into the fish oil issue right now as I'm still undecided as to its essential nature as well as its benefit or harm. To be safe, eat lean seafood, and if you eat fatty seafood make sure its salmon, as the astaxanthin (what makes it pink) is probably protective against oxidation.
Avoiding grains is a good idea for most people, so here, I can get behind paleo diets. Again, grains contain compounds, you can call them toxins if you want, that can harm human health. Some people, based on genetics, diet, and lifestyle, are more susceptible than others, but for most people subjective signs of energy and well being improve when grains are removed from the diet. The exception here would be white rice. With the bran removed there are no toxins present in the endosperm of rice and it is a great source of low toxin starch. Again, this will be used as an energy source for people depending on their current state of metabolic and physiologic health. The same rules that apply for fruit apply here, and for the starchy roots and tubers as well. Rice is generally only problematic for people who have preexisting gut permeability issues, i.e., leaky gut. Even then its usually safe.
Root vegetables (carrots, parsnips, yucca, taro, etc.) are generally considered paleo approved but white potatoes and sweet potatoes generally fall into a gray area. There is an ever increasing movement towards the consumption of sweet potatoes with paleo-type diets and I think for most people that works. They are low toxin foods, although quite high in oxalates so if you are prone to kidney stones watch out, and full of starch, some sugar, and a good amount of vitamins and minerals. White potatoes, while sharing most of those similarities with sweet potatoes, have a dark side. Namely, a glycoalkaloid toxin (defense system) called solanine. Potatoes, unlike sweet potatoes, are part of the nightshade family (Solonaceae) which also includes tomatoes, peppers, paprika, and eggplant, and thus can damage the gut wall and contribute to joint as well as autoimmune problems if an individual is susceptible. But again, if you don't experience negative consequences from eating potatoes they can be a great source of nutrition and carbohydrates depending on your goals.
Not eating any dairy because paleolithic man didn't domesticate and utilize the nutrition the animals are capable of producing is, in my opinion, the largest mistake the paleo community makes. Dairy is actually protective for the gut wall, and if you think about it it makes sense (why would milk harm an infants gut?), by actually closing down gaps or "leakiness," as well as containing an excellent source of protein, vitamins, minerals, fats, and immune enhancing compounds. There are probably people who have a casein sensitivity (major protein contained in milk) but most if not all of those people probably have a gut permeability issue first that dairy then exacerbates. Dairy is probably not causing any of that, although I can't be sure. Some people are also lactose intolerant, which can be remedied by taking enzymes, trying raw milk, drinking fermented beverages like kefir or yogurt, or simply eating cheese, butter, or ghee which are virtually lactose free. Refined dairy proteins like whey are also highly beneficial to the athlete or anyone looking for an immune boost or increased protein intake. Also, because most of the "toxic" compounds that should be avoided from commercial dairy are stored in the fat or contained in the fat, whey, being almost devoid of fat, is probably quite low in those potentially harmful compounds. Dairy is also the only significant source of a short chain fatty acid called butyrate, which besides being the primary fuel for your colonocytes (large intestine cells), improves your immune system, has antiseptic and antiviral properties, and profound positive effects on metabolism. Most of the butyrate produced in the body is from the fermentation of carbohydrates by bacteria in the gut from undigested material like fiber and resistant starch. That being said, if your gut ecology is bad, or you don't eat enough foods containing those bacteria feeding fibers, then your butyrate production is probably inadequate and your body could use a boost from high quality dairy. If you don't like milk or dairy, fine. If you think you're "allergic" or sensitive to it please get a blood test to confirm. But don't not eat it just because the paleo community says you shouldn't.
Not much to say about avoiding beans and legumes. I pretty much agree with it in most instances (just remember that cocao beans aren't beans, they're tropical seeds). However, if the choice is between fast food and junk food or eating a whole food like beans and legumes, then eat the damn beans. The same problems that arise with grains and some plants are found with beans and legumes like lectins, nutrient binders, and enzyme inhibitors. If you do like them or are more on the vegetarian side, which I hope you aren't after reading this, then please soak them and cook them properly to negate some of the defense systems.
Don't eat processed food. Duh. Well, maybe. Sometimes processed food has less of the stuff we want to avoid (toxins) and more of the stuff we want (carbs, protein, or fat, depending) which allows us to eat a greater quantity of calories without the bloat of eating the same calorie content of whole food. This will usually only apply to people working manual labor jobs or athletes doing a large amount of conditioning. For most people, whole foods should be eaten most of the time.
Getting enough sunshine, enough sleep, and enough water are good ideas for everyone, most of the time. The sunshine one and the sleep one are going to be topics of further posts, and water may be as well if there is interest. Hopefully you made it to the end of the post. Sorry about the length but this tends to happen when I write. Hopefully you enjoyed what you read or maybe it really pissed you off or left you confused. All of that is good if it stimulates discussion and thought which is the goal of this blog. I am always open to new information, clarifying a point, or expanding on something I said, and I have no problem amending something if I am wrong.
In good health,
CH
