April 2020



    The constant noise of new diet theories can make every choice seem wrong, but there are tried-and-true ways to achieve good nutrition.

    “How should I eat?” is a question that many Americans ask daily.  Almost everyone seems confused, and no wonder: Splashy new diet theories appear all the time, often countering what we took to be true yesterday.   Consider breakfast, long touted to be the most important daily meal.  Enter intermittent fasting, a popular weight-loss preoccupation and a new justification for waiting until lunchtime for the first day’s meal.   But we have long known that eating a larger breakfast or morning meal actually helps to control weight, directly at odds with the 16-hour fast.

    So, what to do?  Nutritional health is about the kinds of foods we eat, not just their calorie count or when we eat them.  Weight is about energy balance: how the daily intake of fuel that we metabolize aligns with our body’s needs.  “Diet” is a word that has been twisted to mean something that someone invents for the fastest possible weight loss.  There’s always a new one to “go on” for short-term results.  But what diet really means is how you get the nutrition you need throughout your life.  Before the 20th century, humans knew what to eat: Little or no junk (not much existed); animal products in moderation (far less was available); and relatively unprocessed plant foods in abundance.  That’s what almost all traditional diets comprised, though there were variations on this theme that we might now call low-fat, low-carb, vegan, pescatarian and so on.  In eras before that it was even simpler: Humans ate everything we could find that wasn’t poisonous, and as long as we found enough of it in sufficient variety, we generally did fine.   Before there was science, we knew how to do this, just as we knew how to breathe air before analyzing its composition. 

    But beginning in the 19th century and accelerating through the 20th, mass production and marketing of foods began to dominate.  Science and industry combined to find ways to create shelf-stable, nutrient-poor, high-calorie ultra-processed foods, from cheeseburgers to sodas, as well as almost anything you see in a vending machine or next to the checkout counter.   These have generated a public health crisis that requires us to relearn what every human once knew from instinct and experience.    The now-constant barrage of headlines about nutrition science can make us feel like we’re doing everything wrong.  Some people respond by tuning out and continuing to eat what’s familiar.  Others jump on the bandwagon of each thrilling new diet that promises everything.   Most of these deliver temporary results from severe restrictions that no one can maintain.  Rapid weight loss is followed by rapid regain, creating a desperation that makes people eager for the next promise of magic.   The truth is that all good diets feature one or another balanced assemblage of wholesome, real foods, mostly plants.  Even now, with our instincts suppressed, we know what a good diet is. 

    Yet the way we eat is the leading cause of premature death in the U.S. today.  Highly processed foods, especially meats, and added sweeteners and salt are all significant contributors to heart disease and other killers.    Even our comparatively high health care costs are partly due to the damaging effects of unhealthy eating and the pharmaceuticals to treat them.  So how to assess the daily barrage of diet news?  First, we need some perspective on nutritional research.  New findings don’t usually reverse what we knew before; they add context, bit by bit.    Second, we should stop obsessing about particular nutrients, such as whether fat is “good” or not.  The short answer is the unsaturated fats from nuts, seeds, fruits and fish tend to be beneficial, while saturated and trans-fats tend to be detrimental.   Fiber and added sweeteners are simpler to sum up: in our modern habits we badly need more of the former and less of the latter.  But the best approach is to focus on foods rather than to fixate on their components. 

    There is no one best diet.  Good diets can be low or high in fat or carbohydrates, as long as they are made up of wholesome foods, and mostly plants.   The quintessentially healthy Mediterranean diet is high in fat, most of it unsaturated, much of it from olive oil, nuts, seeds and avocado.  But the famous diet of long-lived residents of Okinawa is low in fat because it is centered around diverse vegetables, grains and soybeans, with very limited meat, poultry and fish.   If you adopt an eating pattern that has stood the test of generations, you are almost certain to be better off than with a diet introduced as breaking news.  We are overdue in America for a grown-up conversation about diet for health.  If you agree, pull up a chair.


    Mark Bittman and Dr. David L. Katz, from their book, How to Eat: All Your Food and Diet Questions Answered; essay reprinted from the Wall Street Journal