For some years now, doctors have counseled against eating a diet high in fat, especially saturated fats. However, emerging research suggests that a low-fat diet may not be enough to prevent metabolic syndrome, the collection of factors that increase your risk of stroke, Type 2 diabetes, and coronary artery disease. Some say that overemphasis on cutting fat out of the diet has led to over-consumption of carbohydrates, which itself has contributed to rising rates of obesity, Type 2 diabetes, and coronary artery disease.
On the other hand, a low-carb diet may be more effective than a low-fat diet for preventing heart disease, according to a recent study from the National Institutes of Health. The results of the study suggest that eating a low-carb diet can lead to greater weight loss — regardless of the amount of daily calories consumed — and lower cholesterol levels. The study even suggests that eating a low-carb diet can reduce your risk of having a heart attack in the next 10 years.
Low-Carb Diet Improves Weight Loss, Heart Health
The NIH study, which was recently published in the Annals of Internal Medicine, compared the health effects of a low-carb diet with those of a low-fat diet among a racially diverse group of 150 women and men. The study participants followed their respective diets for one year.
Members of the low-fat diet group followed federal nutrition guidelines by lowering their daily fat intake to less than 30 percent of their total daily caloric consumption. Grains, starches, and other carbohydrates made up about 55 percent of their daily calories, while protein made up the remaining 15 percent.
By contrast, members of the low-carb diet group raised their daily fat intake to about 40 percent of their daily calories, while eating no more than 40 grams of carbohydrates per day. The low-carb dieters were encouraged to eat a diet high in protein and fat, especially unsaturated fats like olive oil, nuts, canola oil, and fish. They were, however, permitted to eat saturated fat. Ultimately, the low-carb dieters consumed about 13 percent of their daily calories from saturated fat, instead of the federally-recommended five to six percent. Most of their fat calories came from unsaturated fats, which are considered healthier.
At the end of the one-year study period, the low-carb dieters showed lower levels of inflammation and lower triglycerides. They showed higher levels of HDL or “good” cholesterol, although levels of LDL or “bad” cholesterol remained about the same. While LDL cholesterol levels, total cholesterol, and blood pressure remained consistent for members of both groups at the end of the study period, the researchers found that those who had been on the low-carb diet lowered their Framingham risk score. The Framingham score calculates your risk of having a heart attack in the next 10 years. The low-fat dieters saw no improvement in this score.
According to the New York Times, some experts think that the difference is in the size and quantity of LDL particles in your bloodstream. A diet high in refined carbohydrates creates more and denser particles of LDL, which are more likely to form arterial plaques. Saturated fat can also raise LDL cholesterol, but it produces fewer and larger LDL particles that are less likely to cling to arterial walls, provided that there aren’t a lot of the smaller, denser particles floating about. Of course, if you’ve already been diagnosed with high cholesterol, you should manage your condition with prescription medication as well as lifestyle changes.
Should You Cut Out Carbs to Protect Your Heart Health?
The results of this study may appear to support the use of low-carb diets to protect against cardiovascular disease, but some experts warn that cutting out an entire type of food from your diet now could have unintended consequences later. Loyola University Medical Center dietitian Kasia Ciaston, MS, RD, LDN, told Medscape Medical News that, when doctors first began warning against high fat consumption 50 or 60 years ago, they had no idea it would ultimately lead to a surge in carbohydrate intake and an increased incidence of Type 2 diabetes and related diseases. Eliminating carbohydrates from your diet could have unintended, but no less serious, health consequences of its own years from now.
“Although I do agree that decreasing carbohydrate intake from processed foods can have wonderful health benefits, I think the real message to get across here is that getting that right balance in your diet is what really helps to create health benefits, versus cutting out a certain macronutrient,” she said.
New research suggests that, despite being higher in saturated fat and fats in general, a low-carb diet may protect against cardiovascular disease. While this may be true in the short term, experts point out that these studies show the health effects of a low-carb diet after only one year. There’s no way of knowing just yet what problems may arise from eating a low-carb diet for decades. Try to avoid processed foods and strike a balance between carbohydrates, fat, and protein for optimum health.