The Worst Type of Fat for Your Health Has Been Identified

Is butter not as bad as we thought? (Photo: Getty Images)

Few nutritional topics have been buzzier in recent years than fats — but according to a new study in the British Medical Journal, while trans fats are still as bad as we all thought, saturated fats aren’t linked to an increased risk of death and heart disease.

First, let’s quickly review the fats that have been making headlines lately:

• There’s been a movement to increase our healthy, monounsaturated and polyunsaturated fat intake, found in superfoods like avocados, almonds and olive oil.
  

• There’s been a push to eliminate all unhealthy, artificial trans fats from our diets, found mainly in processed goods. The FDA announced a plan this summer to nix all trans fats from store shelves by 2018.
  

• And then, there’s the somewhat murkier territory of saturated fats, found in items like cow’s milk, butter, burgers and fried foods.
  

The current research combined systematic review and meta-analysis, with a goal of analyzing higher consumption of saturated and trans fats as opposed to lower consumption. Scientists combed through all observational studies published in medical journals about the effects of these two fats on death, diabetes, and forms of heart disease, including thousands of participants’ data. The research was graded to give more weight to the larger, more-precise studies.

Researchers confirmed that trans fat is indeed detrimental. Intake was associated with a 34 percent greater risk of all-cause mortality, a 28 percent increased risk of cardiovascular disease mortality, and a 21 percent higher risk of developing heart disease in general. However, the scientists didn’t see a clear link between saturated fat and increased risk of mortality, coronary heart disease, cardiovascular disease, ischemic stroke or type-2 diabetes.

So, does that mean we get a free pass on the fried foods and full-fat dairy?

Not at this time, according to study author Russell de Souza, ScD, an assistant professor of Clinical Epidemiology & Biostatistics at McMaster University in Hamilton, ON, Canada, as still more research on fats is required. He says that a large body of evidence shows us there are negative effects associated with excess saturated fat in the diet—which the American Heart Association says should remain at less than five or six percent of total calories consumed, by the way.

“We could not confidently rule out an increased risk of death from heart disease with higher amounts of saturated fat,” de Souza tells Yahoo health. “We should also not ignore stronger and consistent evidence from better-designed studies that eating less saturated fat and more polyunsaturated fat from vegetable oils reduces ‘bad’ cholesterol levels, and that diets that replace saturated fat with these fats, as well as whole grains, reduces the chance of developing or dying from heart disease.”

De Souza says we should still be sticking to low amounts of saturated fat overall, adding in alternatives to reduce intake—items high in plant fats, like olive oils and nuts, as well as whole grains and legumes.

That said, the ultimate message of this research, says de Souza, is that no one nutrient or food is responsible for all heart disease, diabetes, or death. “The whole diet matters,” he explains. “Dietary patterns consistently associated with good health — like the Mediterranean diet, plant-based diets, or the DASH diet — tend to be low in saturated fat, but their healthfulness is not due solely to the fact that they are low in saturated fat.”

Good health is as much about what you do eat as what you don’t, says de Souza, who suggests the well-rounded and highly-nutritious approach. Opt for variety, including whole grains, fruits, legumes, vegetables and nuts, while laying off the refined starches, sugars and processed trans fats.

To boil it down, the advice is still the same: don’t demonize one food or food group, opt for more of the good than the bad, and mix it up to get all your nutrients.