The Physicians Committee

New BMJ Study May Fuel Confusion over “Bad” Fats

  August 11, 2015    
 
 
 

A new study by Canadian researchers may add to confusion over the role of saturated fat—the “bad” fat found in dairy products, meats, and other foods—in risk of heart disease and early death.1

The new study, published in BMJ, was a meta-analysis of 41 previous reports. The statistical analysis was done in two ways, because certain statistical adjustments can influence results. For example, saturated fat increases cholesterol levels which, in turn, can increase cardiovascular risk. If the data are adjusted for cholesterol levels, the link between saturated fat and cardiovascular risk can be made to disappear.

Using unadjusted data, the study found that people whose diets were heaviest in saturated fat had a 12 percent higher risk of developing heart disease and a 20 percent higher risk of dying of it, compared with those whose diets were lowest in saturated fat. Saturated fat was also associated with risk of ischemic stroke. These risks were statistically significant—that is, they were unlikely to be due to chance. The study also showed an increased risk of diabetes, although the findings were not statistically significant (P=0.07). Trans fats—found in many snack foods—were also linked to heart disease.

Using the most adjusted data, however, the risks of saturated fat were largely gone. The study headline and discussion highlighted the most heavily adjusted statistics, and this will likely be the focus of press reports. However, the less-adjusted statistics are more clinically relevant.

The study shows that meta-analyses err on the side of statistical conservatism. Because they rely on the quality of data from the studies they include, real effects often do not appear in meta-analyses.
Although some media reports have recently promoted an “anything goes” attitude when it comes to meats, dairy products, and “bad” fats in general, it is important to remember that these products are as risky as they ever were. In countries, such as China or Japan, whose intake of animal fats has increased, coronary heart disease rates have skyrocketed.

coronary-heart-disease-mortality

1. De Souza RJ, Mente A, Maroleanu A, et al. Intake of saturated and trans unsaturated fatty acids and risk of all cause mortality, cardiovascular disease, and type 2 diabetes: systematic review and meta-analysis of observational studies. BMJ 2015;351:h3978 doi: 10.1136/bmj.h3978

 

Comments

Healthy Fat

from Dr. Barnard newsletter. Research clearly shows that avoiding saturated fat is the best way to keep your heart healthy, despite confusing findings in a new BMJ study.
My question. If coconut oil an (MUFA) healthy oil but with high saturated fat, can I use up to a tablespoon in my morning smoothies?

Dr. Greger covered the issues with coconut oil

I recommend you check out the analysis done by Dr. Greger regarding coconut oil. It does have medium chain fatty acids, but it also has long-chain and short-chain fatty acids. He recommends excluding coconut oil. Personally, I agree with his analysis, though I am no expert, just a layperson interested in evidence-based health.

FATS

25 YEARS AGO I BECAME A VEGETARIAN MOSTLY FOR THE SAKE OF ANIMALS. I URGED FAMILY AND FRIENDS TO JOIN ME. RESULTS 000. I AM NOW 71, WITHOUT ANY CHRONIC OR OTHER DISEASE AND MY VITALS ARE FINE. I TAKE NO MEDICINES. NOT SO FOR TE PEOPLE I REFERENCED. OVER THE LAST 10 YEARS OR SO THEY ALL HAD EITHER A HEART ATTACK, DIABETES, HIGH BLOOD PRESSURE OR CANCER.
WE LOVE DOGS AND CATS. WHY CAN WE NOT LOVE COWS AND PIGS AND CHICKENS, AND FISHES?

@Ron

I guess I'd question your assertion that coconut oil is a healthy fat. What are you aiming for in putting it in your smoothies?

When referring to oils, "Healthy Fat" is nearly an oxymoron.

Ron, why would you want to include any oil in your smoothie? I can understand putting coconut in it, but just oil? The oil is what's left after they remove all the fiber and other solids, and all the water-soluble nutrients. Oil might be worth eating if you're starving and there's nothing else to eat. Otherwise it's pretty much empty calories and not deserving of the label "healthy." All refined oils add calories without nourishment. Eat coconut instead of coconut oil, olives instead of olive oil, and peanuts instead of peanut oil. It'll taste a lot better and you'll be eating whole food instead of fat.

Popcorn

I just started a vegan diet. I really would like some popped popcorn. The oil debate is confusing. Which oil is the best for me to simply pop some popcorn? Thanks for your help!!

Popcorn

Paul, as you may have already found out, air popped popcorn is the best way. You can also put like 1/4 cup or little more in a paper lunch sack fold over the top, and pop for a minute or two till popping slows. Right away, you can t hen mist it with water, vinegar, etc and put on whatever, nutritional yeast a lot of people do, etc.

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