This post is a follow up to a post earlier in the week in which Beth and I decided to accept a 6-week paleo challenge. There are a number of great resources available on what it means to eat paleo and here we will compare and contrast some of the guidance from a few of those related resources.
Loren says that we should be primarily eating lean meats, fruits, vegetables, nuts, and seeds. He recommends trimming meat of excess fat, cooking without excess fat or oil, and limiting eggs to 6-12 per week. Loren recommends eating fruits, vegetables, and nuts, seeds, or healthy oils with every meal unless one is severely overweight or obese, in which case one should limit the amount of fruit (potential for high sugar content) and nuts (high fat content) that he/she consumes.
Foods that Loren says we may consume in moderation include: healthy fats and oils such as olive, avocado, walnut, and flaxseed oils; coffee and tea; alcoholic beverages; and dried fruits and nuts.
Food that Loren recommends we avoid entirely include all dairy products (butter, cheese, cream, milk, yogurt, etc.); all cereal grains and grain-like seeds (buckwheat, quinoa); all legumes (all beans, peas, peanuts, soy and soy products); starchy vegetables (potatoes, cassava, sweet potatoes, yams); salt-containing foods (processed meats, salted spices, many canned goods, many dressings and condiments); fatty meats (bacon, bologna, chicken wings, fatty lamb and pork chops, pork sausage, salami); soft drinks and fruit juices; and sweets (candy, honey, sugars). Loren probably advocates the most restrictive form of the paleo-style diets.
Robb also says that we should be primarily eating meats, fruits, vegetables, and nuts. However, Robb places less of an emphasis on lean meats and more of an emphasis on eating grass-fed or wild-caught meats and fish. Thus, items such as ribeyes, pork chops, ribs, bacon, and lard appear on Robb’s shopping list. Robb also recommends eating a variety of different fruits, vegetables, and nuts, unless one is looking to lose weight, in which case he/she should limit the amount of fruit and nuts they consume. Robb emphasizes that produce should be local, organic, and in season whenever possible.
On fats and oils, Robb advises us to use extra virgin olive oil, coconut oil, avocado (oil and whole fruit), and macadamia (oil and whole nuts) in addition to almonds, pecans, and walnuts. He recommends coffee, tea, and mineral water as your beverages of choice. Another area in which Robb appears to break from Loren Cordain is in the area of (some) starchy vegetables such as squash, yams, and sweet potatoes. Here, Robb places these vegetables on the allowed list, but recommends moderation of these foods by those who are not very active or who are looking to lose weight.
Foods that Robb recommends we avoid entirely include all of the expected paleo no-no’s such as dairy, cereal grains, legumes, high salt-containing foods, soft drinks and fruit juices, and sweets.
Art says that the base of his food pyramid is made of vegetables. He recommends that we should be primarily eating a diet comprised of one-third raw vegetables and fruit, one-third cooked vegetables, and one-third meat or fish. Like Robb, Art includes squash and yams on his list of vegetables, but encourages moderation with the latter. Art also emphasizes trying to eat game meats and organic, grass-fed meats. He also goes beyond Loren by including ham, lamb, and pork on his list of protein to eat.
In line with our previous authors, Art recommends that we exercise moderation in our consumption of fruit by paying attention to portion size and servings per day (no more than 4-5 servings per day). He recommends avoiding bananas, dried fruits, canned fruits, and fruit juice due to the high amount of concentrated sugars in each. He also suggests moderation in the consumption of nuts and recommends almonds, walnuts, and pecans, while avoiding cashews and peanuts. Art appears to be a bit more closely aligned with Loren than is Robb in that Art does not necessarily endorse oils as being good for you, but does recommend olive oil for cooking and salad dressings and omega-3 fish oil for supplementation. Art recommends canola oil for high temperature cooking if absolutely necessary.
Foods that Art recommends we avoid entirely include the same foods that the others list in terms of: grains; dairy (except the occasional cheese or unsweetened yogurt); starchy foods such as potatoes, root vegetables, and yams; other fats such as butter and lard; legumes such as peanuts and soy; high salt-containing foods, non-foods/highly processed foods like snack cakes, etc.
Mark says that we should be primarily eating plant foods as the bulk of our diet. He recommends brightly colored, organic, locally grown vegetables and fruits for maximizing nutritional value. He also recommends eating a variety of organic, grass-fed or wild-caught meats and does not suggest avoiding eggs or animal fats such as butter, lard, or tallow.
Foods that Mark says we should consume in moderation include: nuts, seeds, and their derivative butters; fruits with high sugar content or glycemic loads; coffee; dairy products (he prefers raw, fermented, or high-fat dairy products); fats and oils (with a preference for animal fats); starchy tuber vegetables; and wild rice. Mark also gives us a category of “sensible indulgences” in which he places alcoholic beverages, dark chocolate, and high fat desserts.
Food that Mark recommends we avoid entirely include the usual suspects of grains, legumes, trans and partially hydrogenated fats, processed foods, and sugars.
The Jaminets say that we should be primarily eating plant foods by weight (65% of food should come from plants) and fat by calories (65% of calories should come from fat). Their recommendations are closely aligned with paleo, but focus primarily on being well-nourished and avoiding toxins. They recommend sources of fat with high levels of omega-3 fats (salmon, sardines, and anchovies) and low levels of omega-6 fats (grass-fed beef, grass-fed lamb, seafood, butter from grass-fed animals, coconut oil, palm kernel oil, cocoa butter, and macadamia nut butter). When eating meat that is protein-rich and dry (e.g., chicken breast, some fish) they recommend adding a source of good fats such as coconut oil, pastured butter, or an avocado. The Jaminets also recommend eating “safe starches,” fruits and berries, and vegetables each day. Although our bodies can create sugars from fats and proteins, they do not believe that forcing our bodies to do so (e.g., an active person eating a low-carb diet) put unecessary stress on the body. Safe starches are those that lack fructose, omega-6 fats, and natural toxins, while providing fiber and nutrients – these include taro, sweet potatoes, yams, potatoes, and white rice (which includes rice noodles and rice crackers). It is recommended that you eat as much non-starchy vegetables as you like.
Fruits and berries, like the safe starches, are recommended to be consumed in moderation and are ranked in order of preference with the most preferred fruits and berries being those with the lowest levels of fructose and the most favorable potassium to fructose ratios (e.g., raspberries, papaya, strawberries, and peaches rank high on their list). Nuts (cashews, almonds, and pistachios), oils, and cheeses (cheddar, brie) tend to have higher levels of omega-6 fats than the meats and fats listed above are therefore recommended to be consumed in moderation.
Foods that the Jaminets recommend we avoid entirely include all cereal grains, legumes, vegetable oils, and fructose. You’ll notice that this list overlaps with the previous “foods to avoid” lists, but is more lenient with some dairy (butter, cream), safe starches, and sweets (fruits, berries, etc.) that have low levels of fructose. They argue strongly against the consumption of vegetable and seed oils (calling them liquid devils!) because they contain high levels of omega-6 fats and natural or industrial toxins. These oils include canola oil (a contrast to Art’s guidance), peanut oil, soybean oil, corn oil, wheat germ oil, and safflower oil (you can see how this list therefore excludes most if not all processed foods from your diet). The Jaminets also highlight the toxic effects of fructose and sugar-cured meats.
So, at the end of the day what are we left with? Well, it seems like there is a clear consensus that non-starchy vegetables are a critical part of a good diet and should be consumed freely and regularly. Meat and fish are also unanimously recommended, although there is some difference of opinion with regard to which particular meats and fish to approach or avoid. Bear in mind that when thinking about meat and fish, we can think about: 1) how much fat and protein they contain; 2) saturated vs. poly- vs. mono-unsaturated fats; and 3) ratios of omega-6 to omega-3 fats. We feel that there is sound science to support the decision to seek out sources of meat and fish that are high in omega-3 fats (salmon) and low in omega-6 fats (grass-fed beef and lamb). Among the paleo advocates listed here (perhaps not surprisingly), there is also consensus regarding most of the foods that one should avoid. A paleo diet clearly excludes grains, legumes, processed foods, and sugars.
Then there are the gray areas in which the opinions and the science are not as clear or consistent. These areas include dairy, fruits and berries, nuts, and starchy vegetables. Let’s walk through each of these one at a time. For dairy, the primary offending components appear to be milk sugars (e.g., lactose), proteins (e.g., casein), and hormones or growth factors. This is why those who are more lenient toward dairy tend to allow cream, (clarified) butter, and fermented dairy (yogurt, kefir, some cheeses) into the diet. These products typically have little to no milk sugars left because they have been excluded from the final product (cream) or have been chewed up by bacteria (yogurt). It is also important to bear in mind that dairy products from animals raised on grass will contain more favorable omega-6 to omega-3 ratios of fats than will dairy products from animals raised on grain. Fruits and berries are great for satisfying a paleo sweet tooth, but we have to careful about the types and amounts that we consume. Aim for fewer servings of fruits and berries if you are looking to lose weight and always aim for fruits and berries that have higher levels of nutrients and lower levels of fructose. Nuts are great sources of high density energy and they are portable and convenient. Like fruits and berries, people who are looking to lose weight should limit their consumption of nuts and, like meat and fish, all people should try to eat nuts that have higher levels of omega-3 fats and lower levels of omega-6 fats (e.g., macadamia nuts). Starchy vegetables are a good source of nutrients and carbohydrates for active people. Again, these foods should be consumed with some moderation and we like to scale up or down our consumption of starchy vegetables on the basis of our activity levels throughout the week – high levels of activity permit greater consumption of starchy vegetables, whereas we tend to avoid them more when activity levels are not quite so high.