Fat, once a dirty word when it came to diet, has been edging back toward respectability. New results from a huge international study help continue to reshape its image while at the same time casting doubt on the wisdom of eating lots of carbohydrates and questioning the “more is better” recommendations for eating fruits and vegetables.

The latest evidence comes from data released Tuesday by the international Prospective Urban Rural Epidemiology (PURE) study. Its research team recorded the eating habits of 135,000 adults in 18 countries — including high-income, medium-income, and low-income nations — and followed the participants’ health for more than seven years on average.

Among the PURE participants, those with the highest intake of dietary fat (35 percent of daily calories) were 23 percent less likely to have died during the study period than those with the lowest fat intake (10 percent of calories). The rates of various cardiovascular diseases were essentially the same across fat intake, while strokes were less common among those with a high fat intake.

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Upending conventional wisdom, the findings for carbohydrate intake went in the opposite direction. PURE participants with the highest carbohydrate intake (77 percent of daily calories) were 28 percent more likely to have died than those with the lowest carbohydrate intake (46 percent of calories). The results were presented at the European Society of Cardiology meeting in Barcelona, and published in the Lancet.

“These results point to the fact that human biology is very similar across the globe,” said Dr. Eric Rimm, professor of epidemiology and nutrition at the Harvard T.H. Chan School of Public Health. “It’s not healthy to eat highly processed carbohydrates no matter where you live.”

In a related paper, the PURE results challenged two widely held beliefs about fruits and vegetables. While most dietary guidelines stress the importance of eating more vegetables, among the PURE participants, eating more fruits, and more seeds and beans, was associated with greater benefits than eating more vegetables. Guidelines also tend to stress that if eating some fruits and vegetables is good, more must be better. But among the study participants, those whose diets included three to four servings of fruits and vegetables a day were no more likely to have died as those whose diets included eight or more servings a day.

In a nutshell, a healthy diet based on the PURE results would be rich in fruits, beans, seeds, vegetables, and fats, include dollops of whole grains, and be low in refined carbohydrates and sugars.

“One of the most important take-home messages from the PURE study is that bioactive foods that give rise to new plant life, like fruits and seeds, should be an important part of everyone’s diet,” said Dr. Dariush Mozaffarian, dean of the Tufts Friedman School of Nutrition Science and Policy.

As an observational study, PURE can’t prove cause and effect. In an effort to eliminate the biases that are common in observational studies, the researchers took blood samples from the majority of the study participants and analyzed them for cholesterol and other lipids. Participants with higher intakes of fats, or lower intakes of carbohydrates, had lower levels of low-density lipoprotein (so-called bad cholesterol) and triglycerides, and higher levels of protective high-density lipoprotein (so-called good cholesterol). Those tests help corroborate the main findings.

The PURE results provide strong support for evidence accumulating over the past decade on what makes a healthy diet, said Mozaffarian. “Cutting back on starch and sugar and adding more fat and more foods from plants, especially bioactive fruits and seeds, is where we should be headed,” he said.

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  • Why can I not find the corporate sponsors? I want to know the truth & that is only found when you follow the money.
    Who sponsored the study?

    There is no information about the participants? Age, general health etc.
    Did they all die? Or it it just a calculated guess at the rate of higher risk?

  • What the PURE study does not address is the importance of monounsaturated and Omga-3 fatty acids compared to Omega-6. Considerations of cellular infrastructure including lipid bilayer and cell membrane structure, including organelles in the makeup of the human organism from conception. Diet is both the fuel and material from which we are made and maintained. Every molecule in our bodies is replaced every seven years. The statement regarding bioactive fruits and seeds is really talking about enzymes. Denatured proteins should be minimized in the diet. Glucose polymers are stored as triglycerides composed of saturated fats in adipose tissue.

    • Good to see info re sugars, fats and carbs. Îi loosely follow weight watchers. It is easy to follow

  • I was diagnosed at 43 y/o and 313 lbs as a type II diabetic. I had prided myself on my low-fat, high carb diet. My general practitioner insisted I go on insulin after a low-calorie diet did nothing for my A1C. I put on 30 more pounds in three months!

    I stopped the insulin (while continuing Metformin and Jardiance) and cut out carbs entirely, eating only meat and leafy greens, but to my hearts content. I dropped to 310, started Victoza after seeing an endocrinologist, and was 290 within 6 months and my A1C went from 10 to 7.

    Finally the endocrinologist recommended Gastric Sleeve bariatric surgery. It was laparoscopic, overnight, I could sit and stand the day after surgery (the only pain was lying on my side at night) and was drinking blendered food within a week.

    I have lost 125 lbs since I was 344, am off the meds, eat a small but fulfilling diet of whatever food I like, and am as healthy as I was 30 years ago.

    The low carb diet, Victoza and surgery have added 40 years to my life expectancy by actuarial charts. Don’t put off seeing a good endocrinologist one more second. All you have to lose is three shirt sizes and 12 notches off your belt.

    • An editorial in the American Journal of Public Health in 1984 noted that no medical school here had a nutrition course.

    • Papaya and pineapple contain large amounts of enzymes. Pineapple enzymes are destroyed by cooking.

    • Nearly all enzymes are destroyed by cooking, but who cares? It’s a myth to think you need plant enzymes from food for some reason. Often it’s claimed that without these enzymes, you’ll deplete your own enzymes, but that makes no sense. If your body needs more enzymes, it can just make more. There are enzymes that can be added to food which combat certain digestive disorders (gas and diarrhoea) , but most people don’t need them. Papaya and pineapple are very rich in papain and bromelain, respectively, which can tenderize meat when used in a marinade — but I do a lot of cooking and I’ve never found them useful. What kind of meat are you buying that’s so tough it needs to be tenderized this way?

  • still, something doesn’t add up. Countries like Italy and Japan have among the highest life expectancy and their diet is based mainly on refined complex carbohydrates (pasta and rice). On the other hand, a country like the US has a life expectancy about 10 years shorter than other rich countries, with a diet rich in fats (and probably not accidentally, in sugars).
    Bottom line, it looks to me like the study was a huge waste of money and time, as probably they did not look at the right dietary indicators.

  • this confirms the guidance from cardiologist Arthur Agatston, MD who wrote the South Beach Diet and South Beach Heart books. (No I am not associated with him or any of his businesses in any way.) I read the Heart book over a decade ago and have tried to follow it’s dietary advice since.
    Sugars, including fruit juice (as opposed to whole fruit) and processed carbs (that convert to sugar quickly) are killing people. Travel very carefully through the middle aisles of grocery stores.

  • A distinction should be made between fruit and vegetables. Fruit is high in simple sugars and especially fructose. This causes oxidative stress on the vascular endothelium, which leads to increased risk for cardiovacular disease and type 2 diabetes. Except for its carotenoids and fiber, there’s almost nothing good about fruit. Vegetables are your friend. Eat a carrot.

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