The Great Fat Debate

We recently participated in the annual Food and Nutrition Conference and Expo (FNCE),  organized by the American Dietetic Association. Ten thousand dietitians swarmed the Boston Convention Center for an endless number of education sessions and “healthy” food tastings. One of the most popular sessions was the Great Fat Debate – Is there validity in the age old dietary guidance? [ to reduce fat intake ]

The participants in the panel were prominent nutrition experts:
Walter Willett, MD, DrPH – Chair of the Nutrition Department of Harvard
Dariush Mozaffarian, MD, DrPH, MPH – Harvard Medical School
Alice Lichtenstein, DSc – Senior Scientist, Cardiovascular Nutrition Laboratory, Tufts University
Lewis Kuller, MD, DrPH – Professor of Public Health, Department of Epidemiology, University of Pittsburgh

So what did we learn?

Well, we came out of the session more confused than when we came in.

Here is why: The distinguished experts could not agree as to the damage of saturated fats to our health. They barely agreed on the removal of the recommendation to lower total fat intake from dietary guidelines.

First up, Professor Willett. He presented study after study showing that a reduced fat diet vs. a regular diet showed no substantial differences in weight gain, heart disease, diabetes, or other substantial disease.

Which means the whole “low fat” trend, labeling, and marketing has been a grand mistake. For the last 30 years, manufacturers have removed billions of pounds of fat from our diet, happily replacing them with cheaper carbohydrates, mostly sugars. The biggest nutrition problem now is eating behaviors in the modern diet, Willett said.

His conclusions:

  1. Diets with lower percent of energy from total fat do NOT reduce risk of heart disease, diabetes, cancer, or adiposity (obesity)
  2. The focus on reduction of fat in dietary guidelines has been a massive distraction and can be harmful for some if healthful fats are reduced
  3. Advice about percent of energy from fat should be removed from all dietary guidelines, and total fat should be removed from fat labels

When he dug deeper into the different kinds of fats, he had this to say: we are at saturated fat research today where we were 20 years ago for total fat. OK, let’s wait 20 years and see what we learn?

Professor Mozaffarian presented a series of graphs and charts breaking fats down into saturated fat (SFA), polyunsaturated fats (PUFAs), and monounsaturated fats (MUFAs) and showed that PUFAs and MUFAs are actually beneficial to health. These are the unsaturated fats you’ll find in nuts and seeds, avocado, and olive oil.

His charts, summarizing multiple studies, also showed that saturated fats are far less harmful than once thought. The big problem is that they are being replaced by low quality refined carbohydrates (aka processed foods). Though some studies have shown that replacing saturated fat with unsaturated fat may reduce the risk of heart disease, most people replace saturated fat with bad carbs, which ends up being worse.

His conclusion – the focus on saturated fat is distracting and results in illogical dietary decisions: “what actually is important to improve health in the diet:  increased consumption of fruits, vegetables, nuts, fish, vegetable oils, and whole grains, and reduced consumption of trans fat, salt, and processed meats.”

Dr. Lichtenstein reiterated the message about moderation in fat consumption vs. the massive reduction we’ve witnessed in the last 20-30 years. Regarding saturated fats, her message was that they should be limited in a healthy diet.

Professor Kuller was even more conservative - “There is no scientific evidence for a change in dietary recommendations to reduce cardiovascular disease.” According to Kuller, lower total fat diets such as vegetarian, are the healthiest.

What you need to know:

A quick recap of the 4 positions on saturated fat:

  • Willett – we don’t know enough.
  • Mozaffarian – not as bad as you’d think.
  • Lichtenstein – need to limit.
  • Kuller – limit, as well as limiting total fat.

Confused? We certainly are. But there are a few takeaways from this session:

  • That nutrition science is a work in progress.
  • Replacing fats with refined carbs is not the solution to our dietary woes.
  • Focusing too much on nutrients and not enough on food has not improved the state of America’s diet, perhaps even worsened it.

What to do at the supermarket:

All the scientists agreed that people should change their eating patterns to eat more real food and less processed foods. How does this translate to buying the 95% of foods in the supermarket that do come in boxes?

Our recommendations:

  • Fret less about the total fat, but do look at the saturated fat content.
  • The less ingredients, the better.
  • Portion size plays an important role in the overall fat/ saturated fat intake. An FDA serving size of meat is the size of a pack of cards. Keep that in mind the next time you throw a steak onto the skillet.

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  • Joanna

    I have read interviews with Dr Willett before. I think he is an expert making some very key points about fat that are actually supported by data.

  • Rachel Assuncao

    Thanks for bringing us this incredibly informative recap. It’s always interesting to me, too, how different scientists can look at the research that has been done and arrive at different conclusions. Nutrition is the only science where this can happen :-) .

    The bottom line, for me, is that all 4 speakers agreed that we need to focus on eating real food as much as possible. I suspect they would all agree that a plant-based diet (fruits, veggies and whole grains) supplemented with proteins and fats is the healthy approach. How much protein and from what kind of source? How much fat and from what kind of source? That’s where the bioindividual needs of each person come into play.

  • Ken Leebow

    After considerable research, I believe the focus is on the wrong thing. If you analyze the different types of “diets” — from vegan to meat eater and everything in-between, you will find they they agree on many items to omit from the diet.

    I call it the Circle of Death. If you take these food-types out of your diet, you will not be obese and will be much healthier. Do not eat . . .

    - Fast Food
    - Junk Food
    - Processed Food
    - Sugar – Soda, Candy, etc.

    So, rather than concentrating on fats and carbs, just omit the above items from your circle of death. Everyone seems to know this, however, only a small portion of people are practicing what is preached.

    And of course . . .

    - Add exercise to your daily routine

    Ken Leebow

  • Gerome

    I’m going to take a stab at a better summary.

    “Fats”, the broad category are not bad, and in fact, quite a few are good for you. We cannot think about fats as one thing in our diets. Same goes for carbs: corn syrup is pretty different from whole grain. Transfat and fat in salmon or walnuts are very different.

    Limit your consumption of sat fat. Avoid transfat entirely. Do NOT add crappy calories (often times HFCS) in your quest to cut fat from your products (salad dressings area fine example of low-fat gone berserk).

    Watch your weight and intake.

    Read and understand food labels.

    There is no one cause to anything (good or bad) in nutrition.

    Sidebar — off the subject at hand but on topic.

    Check out this lecture from Harvard Nutrition Conference: Dariush Mozaffarian MD speaks on CV disease risks. If you don’t have time to see the whole thing, the Cliff Notes are that eating a diet that includes whole grain and fruit, the benefits are almost identical to the negatives associated with the risks of high saturated fat diets.{FD6EDE1D-759F-4D31-A162-E3767C12155B}

  • The Wife of a Dairyman

    I agree with Ken, above. It’s all about real food, veggies, meat, dairy, poultry, fish. In our family, it’s everything in moderation. No one of us are obese, we just eat ‘real’ food most of the time. If we choose to have an onion ring once in a while, that’s okay too. But for the most part, exercise on a regular basis, and eat like your great grandparents did:)

  • Jill, The Veggie Queen

    I agree with Ken. An emphasis on real food, mostly plant-based foods makes a huge difference in one’s health.

    And the exercise component is equally critical.

    I did not attend the session but when I spoke with an RD from NYC who did, she summed it up brilliantly, “Don’t eat sh—y food.” That’s a simple message that people can understand, as is my message, “Eat more vegetables.”

  • Elizabeth Jarrard

    Fantastic summary! I think the “debate” just reiterated that we really DON’t know enough about this topic, and the current shifts towards low-fat (high sugar) have definitely not helped America’s health. Research is so divided, and hard to conduct/analyze. There is a fantastic meta-analysis by Siri-Tarino, Sun, Hu, and Krauss (2010), that looked at studies were the endpoint was actual CHD or stroke, not just bio-markers. Their meta-analysis concluded that there is no association of dietary saturated fat on disease prevalence. But most shockingly is examining all the methods of the individual studies. Is one 24-hour recall at baseline, and then follow-up for 23 years really going to show you anything about the individual’s dietary pattern? How can we base our recommendations on research that is so lacking??
    Thanks for the great dialogue!