For over two decades, Dr. David Ludwig has been at the forefront of research into weight control. His groundbreaking studies have contributed to new understandings of the relationship between diet, hormones, metabolism and body weight. Dubbed an “obesity warrior” by Time Magazine, Dr. Ludwig has fought for fundamental policy changes to support a healthier food environment. Professor at Harvard’s Medical School and School of Public Health, David Ludwig is also the Director of the New Balance Foundation Obesity Prevention Center at Boston Children’s Hospital. He has appeared frequently in the national media, including New York Times, Time Magazine, National Public Radio, Public Broadcasting System, Dateline NBC and The Today Show.
Q: I’m very excited about your new book and your take on the conventional wisdom surrounding diet and health. Your book does a great job of explaining complex metabolic processes and debunking accepted, (but misguided), ideas about calories and fat. How did you initially become interested in this area?
A: I began my career in the 1990s, at the height of the low-fat craze. The idea was that since fat has twice the calories as protein or carbohydrates, simply reducing intake of all fats as much as possible would lead to automatic weight loss. Remember the original Food Guide Pyramid of 1992? It had grains at the base (up to 11 servings a day!) and fats at the top, to be eaten sparingly. But I quickly discovered the frustrating reality of obesity treatment – that cutting back on fat and calories rarely led to sustained weight loss.
Fortunately, I had very little formal training in nutrition. Medical schools are notorious for an intense emphasis on drugs while neglecting diet – even though most drugs used today are designed to treat the consequences of a poor diet! My ignorance turned out to be a blessing in disguise, as I wasn’t indoctrinated in the standard approach.
I had decided to specialize in endocrinology, and began to think about nutrition in an entirely different way: Not as a delivery system for calories but instead according to how food affects our hormones, metabolism and even the activity of our genes. This way of thinking has guided my career ever since, in the laboratory and in the clinic.
Q: Can you describe your approach to diet and weight loss and how it differs from conventional diet programs?
A: The conventional approach to weight control focuses on calorie balance. We’ve heard it a thousand times, just eat less and move more. It’s so simple that if someone can’t lose weight, it would seem that they must lack motivation or discipline. But why did the obesity epidemic begin so abruptly around 1980? Did the American public suddenly lose the ability to control themselves?
A 20-year line of investigation in my laboratory, and studies from other groups dating back a century, suggest a basic flaw in this reasoning. Like other basic bodily functions (such as temperature and breathing), weight is determined more by our biology than our willpower over the long term.
When we cut calories the body responds, with increasing hunger and slowing metabolism. The more we restrict ourselves, the more intensely the body fights back. This is a battle few of us can win.
That’s because the basic problem in obesity isn’t too many calories in fat cells, it’s too few in the blood stream and available to fuel the needs of the brain and other organs. In other words: Overeating doesn’t cause us to become fat. The process of becoming fat makes us overeat. From this perspective, we can see why conventional diets are destined to fail.
The program in Always Hungry? targets the underlying problem – fat cells stuck in calorie storage overdrive. With the right diet (and other lifestyle supports) designed to lowers insulin levels, fat cells can be reprogramed to release their excess calorie stores back into the body. When that happens, cravings vanish, metabolism speeds up, and weight loss occurs without the struggle.
Because this approach works with rather than against your body, you get to each until satisfied, snack when hungry, and never count calories again. It’s diet without deprivation.
Q: Tell us about the 3 phases of the program.
A: The diet is the opposite of low-fat – with nuts and nut butters, full fat dairy, rich sauces and spreads, savory proteins and natural carbohydrates. In Phase 1, you’ll give up for just 2 weeks all grain products, potatoes and added sugar (except the small amount in very dark chocolate). But this diet is so rich and satisfying, you won’t miss those fast-digesting (called high glycemic index) carbohydrates at all.
In Phase 2, we add back whole kernel grains, potatoes (except white potato) and a touch of sugar. Then in Phase 3, we mindfully try some of the more processed carbohydrates, based on each person’s ability to tolerate them.
The program also focuses on stress relief, quality sleep and enjoyable physical activities – lifestyle prescriptions that synergize with diet to take weight loss into high gear.
Q: In your book, you describe insulin as a “fat cell fertilizer.” What do you mean by that?
A: Without insulin, we simply can’t gain weight. Children with type 1 diabetes who don’t get enough insulin will invariably lose weight, no matter how much they eat. Conversely, those getting too much insulin become ravenously hungry and gain weight. A key point neglected in most weight loss diets is that the amount of insulin produced by the body varies greatly, based on what we eat. All the highly processed carbohydrates – bread, white rice, potato products, crackers, cookies, juices and added sugars – that crept into our diets during the low-fat craze raise insulin more than any other food, calorie for calorie. The nutrient ratios recommended on the program in Always Hungry? are designed to efficiently lower insulin levels and also calm chronic inflammation, insulin’s troublemaker twin.
Q: I love the “Always Hungry Solution” section of your book where you lay out a plan of action for readers. Does your program also provide benefit to people who don’t need to lose weight?
A: For many people, weight gain is an early sign of an underlying metabolic problem. But others have what’s known as TOFI, Thin Outside Fat Inside – fat cell dysfunction that can greatly raise risk for chronic disease even at relatively normal body weight. Poor diet quality accounts for the majority of chronic disease in the US, far exceeding tobacco use, and that applies throughout the population range of body weight. People with high weight will typically appreciate weight loss as an early benefit of program, but the ultimate goal of the Always Hungry Solution is radiant health and wellbeing.
Q: I agree that healthy food can and should be delicious and the recipes in your book look great. What is your favorite meal (or recipe) from the book?
A: The recipes and meal plans were prepared by my wife Dawn who is a gourmet natural foods chef. So every meal was designed to satisfy your taste buds, in addition to the nutrient targets. One of the runaway favorites among our pilot program participants was the “Shepherd’s Pie” – a Phase 1 dinner. Many people were surprised that we could make that classic favorite with no potatoes at all (we use a cauliflower/white bean puree instead). And as with all of our meals, we also provide a vegetarian option (in this case, with tempeh instead of beef).