The Foods You Were Told to Avoid (But Should Be Eating)

Main Ideas

1. Nutrition Is More Than Individual Nutrients

Dr. Dariush Mozaffarian argues that nutrition advice has often focused too narrowly on single nutrients—such as saturated fat, calories, or sugar—instead of considering foods and how they are made. Foods contain complex combinations of nutrients, fibers, and bioactive compounds that interact with one another and with the gut microbiome. He describes millions of compounds in food that are only beginning to be measured.

The central practical message is to favor diverse, minimally processed foods rather than assuming a food is healthy or unhealthy based on one nutrient or marketing claim.

2. Saturated Fat, Dairy, and “Compared With What?”

Mozaffarian distinguishes between two points: LDL cholesterol is a genuine risk factor for cardiovascular disease, but saturated fat is not a simple stand-in for overall heart risk. Saturated fats vary in their effects, and foods containing them also contain other components that can alter their impact.

• Dairy foods differ. The guest describes a randomized trial in which cream and butter supplied similar amounts of saturated fat, but LDL rose in the butter group and not in the cream group. He attributes this partly to components of the milk fat globule membrane, which remain in cream and cheese but are largely removed in butter-making.
• Whole-fat dairy is not necessarily worse than low-fat dairy. He says evidence generally does not show that whole-fat dairy increases heart disease, diabetes, or weight gain compared with low-fat dairy. Fermented dairy, especially yogurt, may have particular benefits; milk may also have favorable blood-pressure-related effects.
• Butter is a relative choice, not a food to seek out. In his account, butter is a less favorable option than olive, canola, soybean, or other unsaturated plant oils, but may be preferable to refined starches, sweets, or other ultra-processed foods. A small amount is not something to fear.
• The replacement matters. Replacing saturated fat with unsaturated fats may be beneficial; replacing it with refined carbohydrates may not be. He emphasizes evaluating what a food replaces, not just what it contains.

3. Unsaturated Fats and Seed Oils

Mozaffarian strongly challenges the idea that seed oils are inherently harmful.

• Omega-3 fats: He says the strongest evidence among unsaturated fats is for omega-3s, particularly the longer-chain forms found in seafood. Plant sources such as flax and walnuts also provide omega-3s.
• Omega-6 fats: He describes omega-6s as essential and generally beneficial, citing human trials and observational evidence for favorable effects on blood lipids and metabolic measures, without evidence that they promote inflammation in humans.
• Do not lower omega-6 merely to improve the omega-6-to-omega-3 ratio. His recommendation is to increase omega-3 intake rather than cut out another beneficial fat.
• Monounsaturated fats: Olive oil and avocados are presented as healthy foods, though their benefits may involve compounds beyond their fat content. Extra-virgin olive oil contains compounds such as oleocanthal, which he describes as having anti-inflammatory activity.
• Cooking oils: He and Patrick say not to burn oils. Mozaffarian says he uses extra-virgin olive oil for many everyday uses, but canola oil for deep-frying because it is more stable at high temperatures. He considers several plant oils reasonable choices for home cooking.

He also explains that fats are not just calories: they help form cell membranes, affect receptors and gene activity, and serve as precursors to biologically active molecules.

4. Red Meat and Processed Meat Are Not the Same

Mozaffarian places animal foods on a broad hierarchy while emphasizing that overall diet matters.

• He ranks fermented dairy, particularly yogurt, relatively favorably among animal foods, followed by foods such as cheese and milk. Eggs, poultry, and butter come lower in his hierarchy, with unprocessed red meat below them and processed meat at the bottom.
• Unprocessed red meat means fresh or frozen meat without preservatives. He says one or two servings a week is probably reasonable for many people; higher intake may be harmful, especially in the context of a poor-quality diet.
• He says red meat appears more consistently associated with type 2 diabetes and colorectal cancer—particularly cancer in the distal colon—than with heart disease. He discusses heme iron as a potential contributor to oxidative stress and pancreatic damage, along with other compounds formed through meat production, cooking, and interaction with gut microbes.
• Processed meats—such as bacon, sausage, salami, and deli meats—are described as more strongly linked to adverse health outcomes, including cancer, diabetes, and stroke.
• Cooking meat until it is charred or blackened can produce carcinogenic compounds. Patrick raises the possibility that cruciferous vegetables and herbs may mitigate some effects, but Mozaffarian says evidence does not establish exactly how much this changes risk.
• A healthy overall diet may blunt some effects of red meat, including certain microbiome-related markers such as TMAO. He says regenerative, pasture-based production might also affect meat’s inflammatory profile, but more evidence is needed.

5. How Historical Successes Led to Overly Narrow Nutrition Advice

Mozaffarian traces today’s nutrient-focused guidelines to three major developments:

1. Vitamin discoveries: Early nutrition science identified severe deficiency diseases and led to fortification, recommended daily allowances, and dietary guidelines. This was a major public-health success, but it encouraged the idea that complex health problems could be solved by identifying a single nutrient.
2. The Green Revolution: To address famine and population growth, crop breeding and industrial farming dramatically increased yields of wheat, rice, and corn. Mozaffarian says this reduced starvation but also narrowed crop diversity and prioritized yield and resilience over nutrition and taste.
3. The low-fat era: He argues that scientists applied the “single nutrient explains the disease” approach to heart disease, focusing heavily on saturated fat. This helped produce low-fat products that often replaced fat with starch, sugar, and additives.

His broader lesson is that addressing deficiency diseases with individual nutrients is different from managing complex chronic diseases. For those, he argues, the whole food pattern matters.

6. Ultra-Processed Foods and Food Additives

The discussion distinguishes ordinary food processing from ultra-processing. Processing such as baking bread, fermenting yogurt, or canning tuna is not automatically harmful. Ultra-processed foods, in the Nova framework discussed in the episode, commonly contain ingredients and cosmetic additives not typically used in a home kitchen.

Mozaffarian gives several possible reasons ultra-processed foods may harm health:

• They often contain more refined starch, sugar, salt, or combinations designed to be highly palatable.
• Processing can break down the food’s natural cellular structure, making it easier to digest quickly and sending nutrients into the bloodstream rapidly.
• This may leave less material for gut microbes to use and may shift more calories toward absorption by the body rather than microbial fermentation.
• Processing may remove or damage fibers and other food compounds.
• Additives may affect the brain, gut microbiome, or inflammation; some sweeteners have been linked to insulin-resistance effects in human trials.
• Packaging and industrial production can introduce contaminants.

He cautions that not all packaged foods are equally harmful, but says ultra-processing is an important dimension to consider alongside nutrients.

The guest also raises concern about the U.S. GRAS (“generally recognized as safe”) pathway. He claims that many additives enter the food supply without FDA review and that the agency may not know about some of them. He argues for stronger pre-market and post-market oversight, while noting that FDA food and nutrition funding is limited.

7. The Obesity Epidemic: Beyond Willpower and Calorie Counting

Mozaffarian describes obesity as a biological and environmental problem, not simply a failure of discipline.

• He says refined starch intake and ultra-processing rose substantially during the period when obesity first increased.
• He also points to an apparent later puzzle: calorie intake has been relatively flat and physical activity has risen, yet obesity has continued to increase.
• He discusses emerging research suggesting that resting energy expenditure may have declined. One proposed mechanism is reduced thermogenesis—the body’s production of heat—possibly involving brown fat, muscle, and signals produced by gut microbes.
• He suggests that food quality, microbiome changes, and ultra-processing could affect both thermogenesis and how calories are divided between the body and gut microbes. He presents these ideas as developing science, not settled explanations.
• Exercise remains important for health and body composition, but he says it often produces limited weight loss on its own.

For weight management, he recommends focusing on food quality rather than calorie counting alone. He suggests gradual weight loss—around a pound per month for many people—rather than aggressive dieting, which may trigger reductions in energy expenditure.

8. GLP-1 Medications Should Accompany Nutrition and Lifestyle Support

Mozaffarian considers GLP-1 drugs useful for some patients but says they should be used alongside nutrition and lifestyle care, consistent with the adjunctive role he describes in their approval. He warns that many people stop treatment and regain weight. Rapid weight loss can also involve loss of muscle and bone, so he argues that medication should be paired with support that helps preserve health and improve eating habits.

9. Practical Guidance Offered in the Discussion

The guest’s suggested rules of thumb include:

• Choose foods in which you can still recognize the ingredients—for example, visible nuts, seeds, coconut, or dates in a bar.
• When comparing packaged foods, consider the fiber-to-carbohydrate ratio rather than looking only at sugar. He suggests aiming for at least 1 gram of fiber per 10 grams of carbohydrate, with a higher ratio—such as 1:5 or 1:4—being preferable.
• Favor minimally processed plant foods, including fruits, vegetables, legumes, nuts, seeds, and whole grains, along with seafood and appropriate minimally processed animal foods.
• Include sources of healthy fats from plants and seafood; do not treat seed oils as automatically harmful.
• Limit heavily charred meat and keep processed meat intake low.
• Choose dairy based on preference and tolerance; he favors plain yogurt and says whole-fat dairy can be a reasonable option.
• Avoid burning cooking oil. For deep-frying, he favors canola over extra-virgin olive oil, which he says is more prone to burning.
• For weight management, prioritize diet quality and sustainable changes rather than rapid weight loss or calorie restriction alone.

10. Dietary Guidelines and Food Policy

Mozaffarian says recent dietary guidelines represent a shift toward emphasizing real food, reducing processed foods and additives, and embracing healthy fats. He welcomes the recognition that whole-fat dairy can fit into a healthy diet, but warns that food companies may use protein claims to give a health halo to highly processed products.

He argues that improving the food system requires public policy as well as individual choices. His proposals include:

• Increase investment in nutrition research.
• Strengthen FDA review of additives and post-market monitoring.
• Use healthcare programs to fund nutritious food, including food-prescription programs.
• Improve nutrition in federal food programs such as SNAP and school meals while preserving food security and dignity.
• Redirect existing public spending rather than relying only on new taxes.
• Use incentives, grants, loans, or tax breaks to encourage farmers and food businesses to produce and distribute minimally processed, nutritious foods.

He frames “Food is Medicine” as a way to recognize food’s biological effects and role in health—not as a replacement for medical treatment, and not as a claim that food is only medicine. Food also carries cultural, social, and personal meaning.

Speakers and Sources Mentioned

Speakers

• Dr. Rhonda Patrick — host and interviewer.
• Dr. Dariush Mozaffarian — guest; cardiologist, public-health educator, and director of the Food is Medicine Institute at Tufts University.

Researchers, Figures, and Sources Discussed

• Joseph Goldberger — investigated pellagra and argued it was linked to diet.
• Louis Pasteur — referenced in the historical discussion of germ theory.
• Franklin D. Roosevelt — associated with the 1941 National Nutrition Conference for Defense.
• Paul Ehrlich — author of The Population Bomb, discussed in connection with fears of famine.
• Norman Borlaug — plant geneticist associated with the Green Revolution.
• Carlos Monteiro — Brazilian scientist who proposed the Nova classification of food processing.
• Ulf Risérus — researcher associated with the butter-versus-cream trial described by Mozaffarian.
• Bruce Ames — researcher whose nutrient-dense food-bar work is discussed by Patrick.
• David Ludwig — researcher whose trials on diet and resting energy expenditure are discussed.
• Dr. Mozaffarian’s late father — an endocrinologist and researcher, mentioned in the discussion of Persian food traditions.

Institutions, Policies, and Frameworks Mentioned

Tufts University and its Food is Medicine Institute; the FDA; USDA; NIH; the Office of Management and Budget; the Rockefeller Foundation; DuPont; the Institute of Medicine; the GRAS pathway; the Nova food classification; and U.S. dietary guidelines.