Saturated fats have been vilified for decades, while unsaturated fats have been promoted as the heart-healthy fats. Saturated fats are mainly found in animal foods, such as meat, chicken skin, cheeses, whole milk, bacon, butter, heavy cream and eggs. There are also a few vegetable sources of saturated fats, such as coconut, palm and palm kernel oil as well as cocoa butter. A diet high in saturated fats is associated with increased total and LDL cholesterol levels.
Blood Cholesterol Targets
To lower your risk of developing heart disease, it is recommended that you keep your total cholesterol below 200 mg/dL. Regarding LDL cholesterol levels, known as the "bad" cholesterol, the target varies depending on your estimated cardiovascular risk. For healthy people, levels below 130 mg/dL are recommended. People with diabetes or at risk of cardiovascular disease should aim for LDL cholesterol levels of 100 mg/dL or lower, while people at very high risk should get their LDL below 70 mg/dL. As for "good" HDL cholesterol levels, men should aim for levels of 40 mg/dL or higher and women for levels of 50 mg/dL or higher. Triglycerides levels represent another measure of the amount of fat circulating in your blood and these levels should be kept below 150 mg/dL.
Current Recommendations
The American Heart Association recommends reducing saturated fats below 10 percent of the daily calorie intake. For people at increased risk of suffering from heart disease, less than 7 percent of the calories should be provided by saturated fats. This corresponds to a saturated fat intake ranging between 16 and 22g a day based on a 2,000-calorie diet. Avoid trans fatty acids, from shortenings and hydrogenated oils, to keep your blood cholesterol levels within target.
Saturated Fat and Heart Disease
Most health organizations and health professionals advise the population to lower their saturated fat intake to reduce their risk of cardiovascular disease. However, Dr. Ronald M. Krauss, adjunct professor in the Department of Medicine at UCSF and in the Department of Nutritional Sciences at UC Berkeley, and his team conducted a meta-analysis, regrouping 21 studies and more than 300,000 participants. The results, published in January 2010 in the "American Journal of Clinical Nutrition," show that saturated fat intake is not associated with the incidence of coronary heart diseases or cardiovascular diseases. The authors of this meta-analysis suggest investigating the impact on the cardiovascular risk factors of the nutrients used to replace saturated fats in low-fat diets, which often corresponds to carbohydrates.
Beyond LDL Cholesterol Levels
Although eating saturated fats may be linked to increased LDL cholesterol levels, it is important to understand that there are different types of LDL cholesterol. Diets high in saturated fat and low in carbohydrates are associated with large and buoyant LDL particles, which pose a lower cardiovascular risk, according to the August 2005 issue of "Nutrition & Metabolism." On the other hand, low-fat high-carbohydrate diet are associated with small and dense LDL particles, which are more atherogenic and dangerous for your heart health. Unfortunately, LDL particle size is not routinely measured to assess your cardiovascular risk. The triglyceride to HDL cholesterol ratio has been proposed as a powerful predictor of all-cause mortality and cardiovascular events, in the March 2009 issue of the "American Heart Journal." The best dietary modifications you can implement in your diet to improve your triglyceride-to-HDL ratio is not reducing saturated fats, but rather reducing your carbohydrate and sugar intake. Diets with a lower carbohydrate content are associated with a reduction in triglycerides levels and an increase in HDL cholesterol levels, which can help push the triglyceride to HDL cholesterol ratio toward the right direction and lower your cardiovascular risk.
References
- Mayo Clinic: Cholesterol Levels: What Numbers Should You Aim For?
- American Journal of Clinical Nutrition: Meta-Analysis of Prospective Cohort Studies Evaluating the Association of Saturated Fat With Cardiovascular Disease
- Nutrition & Metabolism: The Case for Low Carbohydrate Diets in Diabetes Management
- Annals of Internal Medicine: A Low-Carbohydrate, Ketogenic Diet Versus a Low-Fat Diet To Treat Obesity and Hyperlipidemia
- Health Castle: Good Fats and Bad Fats
- American Heart Association: Step I , Step II and TLC Diets
