Book Review: Eat Right 4 Your Type

Eat Right 4 Your Type
By Peter J. D’Adamo, MD
(G.P. Putnam’s Sons, 1996)
Reviewed by Holly R. Layer, RD


Dr. D’Adamo, a naturopath and physician, asserts that our blood type reflects our “ability to acclimate to different environmental challenges,” including issues with our digestive tracts and immune systems, and influences our risk for certain diseases, our reactions to stress and even the individuality of the bacteria in our GI tract. According to Dr. D’Adamo, Type O hunter-gatherers came first, then Type A developed as our lifestyles became more agrarian, then Type B resulted from the merging of peoples in Africa with those in Europe, Asia and the Americas, and further intermingling of races produced Type AB. He believes that our blood type determines what kind of foods we should eat for optimal health. Specifically, much of the preference for or against a certain food is a blood type’s reaction to lectins, proteins found in food that, according to Dr. D’Adamo, can agglutinate in the body and affect digestion and even lead to other health issues, such as irritable bowel syndrome or cirrhosis.

Synopsis of Diet Plan:

Each blood type includes food recommendations at three tiers (highly beneficial, neutral, avoid) for each food group, and portions per week based on ancestry (African, Caucasian, Asian). Strategies for weight loss—while not the sole purpose of the book—is part of each type’s recommendations. Also included are beverage, spice and condiment recommendations, a three-day sample meal plan and approximately 10-15 recipes. Additionally, he recommends different supplements, stress management, exercise suggestions and a note on each type’s ‘personality.’

Type O = meat-eater

As the ‘original’ blood type and hunter-gatherer, Dr. D’Adamo claims that Type O’s have not only more stomach acid but also a greater ability to digest both fat and protein well. On the flip side, he says, carbohydrates—namely those from grains—are not as well digested and turned into fat and increase inflammation in the body. Type O’s are to eat red meat, poultry and seafood, very little dairy, lots of nuts and seeds, as well as almost all vegetables, except those in the Brassica family (cabbage, cauliflower, etc..). Foods to avoid include most beans, cereals, grains, breads and pastas. Coffee is to be avoided as it leads to increased levels of stomach acid, which Type O’s don’t need. Because of Type O’s high response to stress, exercise is essential, and high-intensity activities, such as aerobics, cycling and contact sports are recommended for 30-60 minutes three to four times a week. (Author’s note: Prior to reading this book, I gravitated to a mostly ‘paleo-style’ diet—heavy on meat, eggs, fruits and vegetables—while limiting grains and dairy—and engaging in high-intensity exercise, such as running, cycling and kickbox, because that diet and exercise regimen make me feel the most healthy. I am Type O.)

Type A = vegetarian

According to Dr. D’Adamo, Type A stomach acid makeup favors the digestion of carbohydrates over protein and fat. He recommends an all/mostly vegetarian diet for Type A, but does allow some fish for those of Caucasian and Asian descent. Wheat and grains are beneficial for Type A, with up to 10 one-cup portions of whole grains allowed per week. He also recommends eating mostly raw, organic fruits and vegetables. For stress relief and exercise, Dr. D’Adamo recommends calming, relaxing activities, such as yoga or walking, and claims that “highly competitive sports and exercises…exhaust your nervous energy…and leave your immune system open to illness or disease.”

Type B = flexitarian

Dr. D’Adamo says Type B’s tend to produce high levels of cortisol, which can lead to higher levels of inflammation and a greater risk for disease. The recommended diet is a mix of meat and plants, but chicken should be avoided, as well as corn, wheat, tomatoes and peanuts, which promote weight gain. Recommended red meats include lamb, rabbit and venison. Other recommended foods include green vegetables, eggs and low-fat dairy. Exercise recommendations for Type B focus on both mental and physical activities, such as golf, martial arts and hiking.

Type AB = A + B (mostly)

The book claims that those with Type AB blood can usually stick to a combination of the recommendations for Types A and B. If a food isn’t recommended for either type, it’s mostly likely not recommended for AB. There is an exception for a specific type of lectin, an example of which is the tomato. According to Dr. D’Adamo, Type AB’s are more energetic than A’s, their immune systems are more ‘tolerant,’ but their digestive tracts are more ‘sensitive’ and that while they have sufficient stomach acid to digest meat, it tends to get stored as fat. Recommended foods for Type AB include seafood, green vegetables and dairy, especially yogurt and kefir. Dr. D’Adamo claims cured meats can cause stomach cancer in this blood type. Smaller, more frequent meals may help digestion, and a mixture of calming and more intense exercise is recommended.

Nutritional Pros and Cons:

On the upside, Dr. D’Adamo recommends only real, whole foods and even provides correct portion sizes and frequency per week. Every blood type benefits, he says, from fruits and vegetables, therefore each recommended diet is sufficient in vitamins, minerals and fiber. Fish is also recommended for each diet. However, as almost-vegetarians, Type A’s may need to ensure they eat proper protein sources and variety, not to mention that some Type A readers may not even WANT to become vegetarians. Additionally, while his ‘highly beneficial/neutral/avoid’ list is easy to understand, it might be too restrictive for some readers. In order to ease the transition, Dr. D’Adamo even provides a four-week elimination plan for each blood type. Readers should consult their doctor before beginning a supplement regimen beyond a basic multivitamin. Lastly, Dr. D’Adamo’s recognition of the importance of stress-relief and exercise for overall health is commendable, even if readers don’t all fit into his blood-type boxes.

Bottom Line:

There is no scientific evidence, or even much support for Dr. D’Adamo’s claims, and there is even evidence to suggest that Type A was the original blood type, not O like the author suggests. That being said, the diet itself isn’t harmful. Eating lots of fruits, vegetables and lean meats is a good idea for almost all readers. Highly motivated readers may ’buy-in’ to the importance of individualizing their diet by their blood type; however, they should not forget that there are more important factors to include when adjusting their diet, such as their own medical history, weight loss needs (if any) and preferences. Dr. D’Adamo’s recommended food lists seem arbitrary at best, and should not discourage participants from eating healthy options even if they appear on an ‘avoid’ list.

Each blood type includes approx. 10-12 recipes and a three-day sample menu.

Book Review: The Campbell Plan

The Campbell Plan: The Simple Way to Lose Wight and Reverse Illness, using The China Study’s Whole-Food, Plant-Based Diet
By Thomas Campbell, MD
Rodale (2015)
Reviewed by Holly R. Layer, RD


The Campbell Plan uses the findings of The China Study, of which both Campbell and his father (T. Colin Campbell, PhD) were part, to assert that a plant-based diet can not only allow readers to be the healthiest they can be, but also to fend off diseases, including cancer. The findings are based on the results of the 20-year China Project, which studied the diets of 65,000 adults in 65 counties in China and rates of disease. They concluded that the counties eating higher animal protein had more incidences of ‘Western’ diseases and cancers than those populations eating a plant-based diet. Campbell’s own studies on tumor growth and protein intake (casein, found in milk) in lab rats led him to conclude that consumption of animal protein promotes tumor growth.

Campbell says, “…humans eating lesser amounts of animal protein and more plant-based foods might have not only more energy, but also lower odds of developing obesity, diabetes, high blood pressure, heart disease, kidney disease, liver disease, brain disease and prostate, breast and colon cancers.” Additionally, he claims that a plant-based diet promotes healthier bacterial communities in the gut. The book includes chapters addressing ‘hot topics’ such as soy and gluten.

Synopsis of Diet Plan:

Campbell believes a high-carb, low-fat diet high in fiber, along with exercise, is the healthiest way to eat. He says, “…if you make the right food choices, you will do more to improve your health than anything else you might do.” But what are his ‘right food choices?’

The biggies to avoid are all animal products (meat, eggs and dairy). Additionally, he includes lists of foods to eliminate, including, pure fats (liquid oils, butter, margarine, substitutes), refined grain products, processed foods, cereals with added sugars, artificial sweeteners, and jarred sauces/dressings with added oils. Recommended foods include fruit, 100% whole-wheat pastas, breads, beans, vegetables, and nutritional yeast.

Campbell’s diet plan, as he presents it in the book, is really a lifestyle change. Campbell does not encourage counting calories or other macronutrients, nor is this a weight-loss plan. He fully intends that readers embrace a ‘no animal products’ eating style for good.

Nutritional Pros and Cons:

All of the foods Campbell recommends are full of health benefits; fruits and vegetables are low in calories and high in vitamins and minerals and whole grains are packed with fiber. But by eliminating both meat and dairy, protein may be lacking in the diet. Campbell states that 12.5 grams of protein per 500 calories is sufficient for most adults, which equates to approximately 50 grams of protein in a 2,000-calorie diet, which does align with the FDA’s protein recommendations as well. However, diet quality determines the amount of protein—and other nutrients—taken in, and not all participants will eat the amount or variety needed to meet their protein needs without meat and dairy. Campbell does make a case for allowing ‘small amounts’ of lean meat and eggs, but only for someone who has followed his ‘optimal diet’ since birth, which is highly unlikely.

Campbell also includes hints for grocery-shopping, label-reading, substitution suggestions and advice on how to discuss your dietary change with others. He addresses added sugars, salt and fat, and discourages the use of ‘vegan’ meat/cheese/mayo, etc… substitutes. A two-week sample meal plan is included that features recipes from the book.

Bottom Line:

Despite its very restrictive nature, there is a lot to like about the book and its presentation. Campbell, above all else, recommends eating real food—whole grains, vegetables, fruit and legumes—and ditching anything even remotely processed. He also addresses many dietary ‘ills’, like added sugars and trans fats, information beneficial to anyone, not just those ready to swear off animal products.

The book is well referenced, although further research reveals that there are holes in the data, or places in which pertinent data may have been omitted. For example, one of Campbell’s biggest and earliest points is that casein, a protein found in cow’s milk, promotes tumor growth. Not mentioned in the book is that whey, the other protein found in cow’s milk, has a protective effect and delays tumor growth, and that both of these proteins are most often ingested together. Additionally, studies have found that indigenous populations whose diets are high in animal products, such as the Greenland Eskimo, also have very low rates of disease and cancer, despite their animal protein intake. Overall, Campbell makes some broad generalizations, such as the casein example and that high cholesterol is a marker for all manner of disease, that aren’t fully supported by existing research. Follow his advice for eating real, whole foods, making most of your diet plant-based and his guidance for avoiding added sugars, etc… but staying away from all animal products on the basis they are the cause of disease is unfounded.

This book includes 55 recipes and a two-week sample menu.

Book Review: The Paleo Diet

The Paleo Diet: Revised Edition
By Loren Cordain
John Wiley & Sons (2011)
Reviewed by Holly R. Layer, RD


The idea of ‘paleolithic eating’ emerged in the 1970s after research by a gastroenterologist and was first popularized by Loren Cordain, in his initial 2002 book. This revised edition includes updated research and slightly different recommendations for types of oils to consume, saturated fat and the increased benefit of the Paleo diet for those with autoimmune diseases.

Cordain writes that our “genes determine our nutritional needs,” and that our “genes were shaped by selective pressures of our paleolithic environment.” Thus, we are healthier when we eat the way our ancient hunter-gatherer ancestors did. In fact, Cordain claims that indigenous peoples were almost disease and ailment-free, citing that while hypertension is the greatest risk to Americans, the Greenland Eskimoes, studied in the 1960s and 1970s, were found to be free from heart disease despite their diet high (60%) in animal foods. Cordain calls becoming lean and fit like our ancestors “our birthright.”

Synopsis of Diet Plan:

Cordain lays out the six ‘ground rules’ for the Paleo Diet, which are based on a ‘Stone Age’ diet: ‘Eat lots of lean meats, fresh fruits and vegetables.’ Cereals/grains, legumes, dairy and processed foods are out. Seven ‘keys’ of the diet elaborate on the foundation of the diet, addressing protein and carbohydrate intakes, fiber, fat, potassium and sodium, pH and vitamins and minerals.

Understanding that many readers may balk at the thought of omitting so many staples of their current diet, Cordain provides three ‘levels’ for those attempting to go Paleo: an ‘entry’ level in which three meals a week are non-paleo, a ‘maintenance’ level in which two meals per week are non-paleo, and the ‘maximal weight loss’ level in which only one meal per week is non-paleo.

While the book and eating plan themselves are not primarily focused on weight-loss, Cordain all but guarantees that adopting a paleo eating plan will promote weight loss, and dedicates a chapter to weight-loss success stories.

Nutritional Pros and Cons:

Cordain compares both a Paleo diet and the typical American diet side-by-side to see how they stack up on the Recommended Daily Allowances (RDAs). Unsurprisingly, the paleo meals—including Atlantic salmon, spinach salad, pork chops and steamed broccoli—outranked provided more than 100% in every category, while the American provided more than 80% in only seven of the 22 categories.

The book includes exercise recommendations and a ‘user’s manual,’ that includes information about eating and shopping for wild game meat and fish, the difference between and beneficial ratio of omega-6 to omega-3 fats in nuts and seeds, as well as helpful hints for dining out or traveling.

The book does address the acid-base loads of foods, and encourages readers to eat more alkaline foods as our typical diets contain more acidic foods that tax our kidneys. This may be too confusing a concept for most readers and remains to be proven as beneficial to our health.

Bottom Line:

While the book’s 25-page bibliography of references is extensive, there are no footnotes or easy way to cross-reference the particular study that corresponds to a particular claim. The Paleo Diet is as faddish a diet as they come, omitting not one but two entire food groups. However, a paleo eating style does promote the consumption of lean meats, healthy fats and plenty of fruits and vegetables, at the very expense of junk and processed foods. Admittedly, both food groups on the chopping block—grains and dairy—are not vital in our diets (as we can get all the vitamins, minerals, fiber and even calcium from fruits and vegetables), and often make up most of the less-nutritious foods we eat, such as crackers or cakes or sweetened yogurts. Readers should be encouraged to adopt some of the healthy principles in the book, either by trying one of the outlined diet ‘levels’ or by simply allowing ‘real’ food to crowd out sweetened grains and dairy (and other processed foods) on their plates.

This book contains approximately 75 recipes and three sample two-week meal plans.