Life Extension Magazine®

Farmer showing vegetables a part of the whole food diet

The Whole Foods Diet

Discussing his new book, The Whole Foods Diet: The Lifesaving Plan for Health and Longevity, Whole Foods Market cofounder John Mackey explores the link between a plant-based diet and reducing disease and obesity.

Scientifically reviewed by Dr. Gary Gonzalez, MD, in August 2023. Written by: Garry Messick.

For John Mackey, the cofounder of the Whole Foods Market chain, which was recently sold to Amazon, healthy eating represents something more than just a business model focused on a specific consumer group. Mackey has translated that passion into a new book, The Whole Foods Diet: The Lifesaving Plan for Health and Longevity.

In his book, written in collaboration with physicians Dr. Alona Pulde and Dr. Matthew Lederman, Mackey simplifies the technical aspects of nutritional science in favor of giving readers practical, highly readable information regarding the benefits of a whole food, plant-based diet and helping them to make informed food choices. He also tackles subjects such as customizing diets for particular tastes and the ethical and environmental consequences of moving away from processed foods toward organic whole foods.

For this illuminating discussion with Life Extension®, Mackey explores diet in relation to disease and obesity, provides an explanation of what constitutes whole foods, and covers some of his recommendations for foods that should be included in a healthful diet.

LE: What’s your view of the current problem of obesity?

JM: There is an unavoidable connection between excess weight and a host of chronic conditions that all of us would rather avoid. Gaining weight is often the first warning sign that chronic disease is building up under the surface of your body. “Weight sits like a spider at the center of an intricate, tangled web of health and disease,” writes Harvard Medical School’s Dr. Walter Willett. Strands in that web include heart disease, strokes, several types of cancer, diabetes, arthritis, and many more unpleasant and sometimes life-threatening conditions. Maintaining a healthy body weight is therefore in our best interests if we want to remain vital, active, and glowing with the beauty that good health conveys, for decades to come.

This is not to say that a healthy weight is a guarantee of health. If you’re someone who maintains a lean body without much effort, you may think you’re better off, but it’s not necessarily true. You could still have heart disease, diabetes, or cancer developing in your body, even though you don’t have a visible warning sign telling you how sick you are. I’m sure you’ve heard stories of the seemingly “thin and healthy” people who are suddenly struck down by diseases they didn’t appear to be at risk for.

LE: What sorts of dietary tendencies are most associated with diseases?

JM: High consumption of red meat and processed meats has been connected with greater risk of death from all causes, including chronic diseases such as cardiovascular disease and type II diabetes. Eating large amounts of animal protein has been correlated with higher incidences of cancer and mortality. Over a thousand studies on bowel cancer risk have confirmed that red meat increases risk while high-fiber plant foods decrease it. Processed meats are particularly scary, with significant studies linking them to stomach cancer, breast cancer, and colon cancer, and the World Health Organization classifying them as a carcinogen. As a result, the World Cancer Research Fund International and the American Institute for Cancer Research came out with firm recommendations for people to “eat mostly foods of plant origin,” including whole grains, fruits vegetables, and beans.

These studies are not merely outliers. In fact, they are just a few among a multitude of compelling data points that make the case for a whole foods, plant-based diet. The research supporting the wisdom of this way of eating, even briefly summarized, is enough to fill several books. Rigorous laboratory experiments, carefully controlled clinical trials, and long-term observational studies following millions of people over several decades confirm the profound value of eating more real, plant-based foods and minimizing highly processed foods and animal products.

LE: How do you define “whole foods?”

JM: These are “real foods.” These foods are essentially intact, close to the form in which they grew. None of their essential nutritious parts have been removed, and no unhealthy substances have been added to them. This includes all types of whole fruits and vegetables, whole grains, beans and other legumes, and nuts and seeds, as well as unprocessed animal foods. You’ll often find unprocessed foods in the perimeter aisles of the grocery store, as well as at the farmer’s market. They usually don’t need much if any packaging, nor do they feature long ingredient lists. They won’t contain preservatives, and many of them will need to be kept in the refrigerator and consumed soon after purchase, unless they’ve been dried, like beans and whole grains, or purchased frozen.

LE: The main food group you encourage people to eat are plant foods. How prominent should they be in the average person’s diet?

JM: Some people, for ethical reasons, may choose not to eat any animal products, or only to eat dairy products and eggs. Putting aside the ethical issues for now, from a health perspective, our recommendation is that plants should make up at least 90% of your overall calorie intake.

LE: What’s your advice for those who want to include animal products in their diet?

JM: If you choose to eat animal foods, keep in mind the way in which the animals are raised. Modern industrial factory farming has made animal foods widely available and affordable, but it comes at significant cost—both to the well-being of the animals and to your health. From a health perspective, common practices that are cause for concern include treating livestock with antibiotics and growth hormones, and feeding them corn and other products that are far removed from their natural diet.

We recommend that you follow these guidelines if you choose to eat animal foods: Choose grass-fed, organic, antibiotic-free meat and dairy products, and pasture-raised chickens and eggs.

Choose wild-caught fish and seafood where possible, and avoid those more likely to contain toxins such as mercury. Species to avoid tend to be those that are longer-lived and higher up on the food chain, including tuna, swordfish, and king mackerel.

Avoid processed meats. The World Health Organization recently categorized processed meats as a Group 1 carcinogen, alongside cigarettes and asbestos. If you decide to eat meat, choose unprocessed forms and stay away from hot dogs, salami, bologna, bacon, ham, and the like.


LE: In your book you list what you call the “Essential Eight” food groups: whole grains and starchy vegetables, beans and other legumes, berries, other fruits, cruciferous vegetables, leafy greens, nonstarchy vegetables, and nuts and seeds. Comment, if you would, on a few of these—cruciferous vegetables, for instance.

JM: The cruciferous family of vegetables, also known as brassica vegetables, includes broccoli, radishes, cabbage, collard greens, Brussels sprouts, cauliflower, artichokes, arugula, and kale. Not only are these diverse foods all related, they also share some extraordinary health benefits, particularly when it comes to preventing cancer. In fact, Dr. Joel Fuhrman points out that cruciferous vegetables are the most micronutrient dense of all vegetables, and calls them “the most powerful anticancer foods in existence.”

This latter distinction may be due to a potent cancer fighter that is unique and particularly important to this group of foods, a family of substances known as glucosinolates. Glucosinolates are responsible for the pungent aroma and bitter flavor of many cruciferous vegetables. When these glucosinolates are broken down, either during food preparation or through chewing and digestion, they form compounds called isothiocyanates and indoles that have been shown in numerous studies to inhibit the development of cancer.

LE: Any serving suggestions, particularly for those who don’t have a taste for these veggeies?

JM: It turns out moms all over America are right when they tell kids, “Eat your broccoli!” The good news is, there are creative ways to eat broccoli and other cruciferous vegetables that your mom may not have known about. Raw or lightly steamed broccoli or cauliflower florets add a satisfying crunch to a salad or dipped in hummus. Kale can be blended raw into smoothies, “massaged” into a salad, or lightly steamed with some garlic and lemon juice. Zesty radishes, thinly sliced, add bite to salads, while the peppery flavor of arugula makes a nice change from lettuce.

You can also try tossing in a few handfuls of raw arugula into your warm pasta with veggies, letting it wilt just a little. Bok choy is a lovely addition to stir-fries, with its combination of crunchy stalks and tender leaves. Add it right at the end, as it needs only a couple of minutes to cook.

LE: How about leafy greens?

JM: Some fall into the cruciferous category, like kale, collards, arugula, and bok choy. Other particularly potent greens include watercress, Swiss chard, spinach, romaine, and other salad greens.

Researchers at Harvard University found greens to be the food most highly associated with protection from major chronic disease and cardiovascular disease. They have also been associated with reduced risk of diabetes. Greens are packed with fiber, protein, and antioxidants, as well as disease-fighting phytochemicals.

You can eat your greens raw as a salad, add handfuls to a smoothie, steam them lightly and serve them with lemon juice, toss them into a soup or stew at the end so they lightly wilt, blend them into flavorful pesto-style sauces, add steamed greens to mashed potatoes, or water-sauté them with garlic. Spinach makes a great addition to homemade hummus or other bean spreads. Greens are so extraordinarily healthy that we try to add them whenever possible to the dishes we cook. Try to eat greens every day!

LE: Nuts and seeds?

JM: Nuts and seeds are packed with health-promoting nutrients and consistently associated with good health outcomes. They are a rich source of all kinds of nutrients—understandable, given that they contain the energy to create an entire plant or tree.

Indeed, the consumption of nuts and seeds has been associated with reduced risk of heart disease and diabetes, as well as an increased lifespan. While some people raise concerns about the relatively high calorie density of nuts, they are also extremely filling and are generally not associated with an increase in weight or BMI. Having said that, if you are trying to lose weight, you might want to limit your nut and seed intake to less than a handful a day.

LE: Could you elaborate on the differences between whole carbohydrates and processed carbohydrates?

JM: One of the things many people love about a whole foods, plant-based diet is that it includes the comforting starchy “carb” foods…sweet and earthy yams, hearty winter squashes, tender juicy corn, and even the much-loved potato, as well as all the varieties of tasty, satisfying whole grains, can find a regular place on the whole foodie plate. In this category we also include the grainlike seeds, such as quinoa, millet, amaranth, buckwheat, and teff, which are nutritionally similar to grains.

The important and often-missed distinction between whole carbohydrates, like whole grains and starchy vegetables, and highly processed, refined carbohydrates (is that) while the latter are to be avoided, the former play a key role in an optimum diet.

Carbohydrates are the best energy source human beings have available, and over the course of evolution, our bodies have adapted to be able to metabolize them efficiently. Whole grains provide fiber, protein, essential fatty acids, and numerous phytochemicals, as well as carbohydrates, in the perfect package to give us the energy we need. They have been linked to lower risk of heart disease, diabetes, obesity, certain cancers, and mortality from all causes. Eating whole grains also improves bowel health, helping to maintain regular bowel movements and promote growth of healthy gut bacteria.

Contrary to popular opinion, carbs in the form of whole grains can actually help you lose weight. Whole grains and starchy vegetables leave you feeling full and satisfied, and therefore combat snacking and overeating, actually preventing you from becoming or remaining overweight.

LE: Finally, what’s your advice to someone attempting to drop unhealthy, processed and sugary foods in favor of a healthy diet?

JM: Eat enough! One of the most common reasons people struggle in the transition to a whole foods, plant-based diet is that they don’t eat enough. That’s right. You’re much more likely to fail from eating too little than from eating too much. Many people start out by focusing on what they shouldn’t eat and don’t give enough attention to all the good things they should be eating. Because whole plant foods are less calorie dense than highly processed foods and animal foods, you may need to eat larger portions or more frequently than you are accustomed to. Try to include as many of the Essential Eight in your everyday diet as possible, and particularly focus on the starchy vegetables, whole grains, and legumes.

The Whole Foods Diet  

Listen to your body, especially in the early days of your transition. If you’re feeling hungry again only a couple of hours after eating, you probably didn’t have a big enough meal or include enough satiating whole grains or starchy vegetables. If you feel satisfied and content, stop eating, but if not, eat more. There is no right or wrong time to eat, only right and wrong foods. You can now trust your hunger signals without fear of overconsuming calories. You’re no longer in a battle with your body or your cravings—so long as the only food on your plate is real food (particularly of the whole food, plant-based variety).

If you have any questions on the scientific content of this article, please call a Life Extension® Wellness Specialist at 1-866-864-3027.

The Whole Foods Diet is available from bookstores and online retailers.