Diet for Dyslipidemia

A modified diet can improve the lipoprotein and lipid levels of individuals with dyslipidemia and can help prevent and/or slow the progression of CHD.
Mahitab Hany, BS Pharm, PGDipClinPharm, PGDipClinNutrition

OVERVIEW ã…¡ Dyslipidemia refers to high blood levels of low-density lipoprotein cholesterol (LDL-C), triglycerides (TGs) or both, or low blood levels of high-density lipoprotein cholesterol (HDL-C), all of which contribute to the development of atherosclerosis. Causes may be primary (genetic) or secondary, which includes excessive dietary intake of saturated fat, cholesterol and trans fat. A modified diet can improve the lipoprotein and lipid levels of individuals with dyslipidemia and can help prevent and/or slow the progression of coronary heart disease (CHD).

          Lowering total cholesterol and LDL-C decreases risk for fatal and nonfatal coronary events. The 2016 update of the Canadian Cardiovascular Society guidelines for the management of dyslipidemia for the prevention of cardiovascular disease in the adult has established target lipid values based on degree of risk of CHD.

Note (1)
The guidelines recommend the following dietary measures to help achieve these target values...

TYPE OF FATS

TRANS FATS are formed from the partial hydrogenation of vegetable oils, which turns the oils into solids. Trans fats have been shown to raise LDL-C levels and decrease HDL-C levels. These fats are often listed as ‘partially hydrogenated oil’ on food labels and are often found in vegetable oil shortening, hard margarines, commercially prepared baked goods, potato and corn chips, crackers, microwave popcorn and deep-fried foods. The Heart and Stroke Foundation of Canada states that trans fats are at least 5 times more harmful than saturated fats and has appealed to Health Canada to introduce regulations to severely limit the trans fat content of foods.

CHOLESTEROL is primarily produced by the liver, but dietary cholesterol found in animal foods may contribute to elevated blood cholesterol levels. Foods that have high levels of dietary cholesterol include egg yolks and organ meats, but all animal products contribute to the cholesterol level of the diet. Every ounce of beef, lamb, pork, poultry and fish contains approximately 25 mg of dietary cholesterol, and 1 cup of milk contains 4–33 mg, depending on the fat content. Restricting dietary cholesterol intake can achieve a 1–3% reduction in LDL-C.

SATURATED FATS are the strongest contributor to elevated LDL-C levels. They are found primarily in animal foods (beef, chicken, pork, whole-fat dairy products, eggs and lard) and in some plant-based foods (coconut, palm and palm kernel oils and cocoa butter). Restricting saturated fat intake can achieve a 5–10% reduction in LDL-C. A large, prospective cohort study found that replacing 5% of energy intake from saturated fats with equivalent energy intake from polyunsaturated fats, monounsaturated fats or carbohydrates from whole grains was associated with a 25%, 15% and 9% lower risk of CHD, respectively. However, carbohydrates from refined starches or added sugars (e.g., sugar sweetened beverages or foods) have been positively associated with a risk of CHD and should not be used to replaced saturated fat.

UNSATURATED FATS include monounsaturated and polyunsaturated fats. Monounsaturated fats (MUFAs) include omega-7 (palmitoleic) and omega-9 (oleic). They have been shown to improve blood cholesterol levels and are found in avocados, nuts and vegetable oils (canola, olive, peanut, safflower, sesame and sunflower).

POLYUNSATURATED FATS (PUFAs) include both omega-3 and omega-6 fatty acids. Omega-3 fatty acids can lower triglycerides and help prevent clotting of blood. They are found in cold-water fish (mackerel, herring, sardines, salmon and trout), canola and soybean oils, nuts (walnuts, pecans, pine nuts), and seeds (flaxseed, sunflower seed). Omega-6 fatty acids lower LDL-C. They are found in vegetable oils (soybean, safflower, sunflower, corn), non-hydrogenated margarine, nuts (almonds, pecans, brazil nuts) and seeds (sunflower).

NOTE (2)
  • Fat free: < 0.5 g fat per serving of stated size.
  • Low fat: ≤ 3 g fat per serving of stated size.
  • Reduced fat: modified to contain at least 25% less fat than a similar reference food.
  • Light in fat: modified to contain at least 25% less fat than a similar reference food.

Beware of potentially misleading labels, such as...
  • Cholesterol free, as only animal products contain cholesterol.
  • Partially hydrogenated fat, as trans fats are formed in the processing.
  • Low fat, as fat may be replaced with refined carbohydrates (sugars) and the resulting product may be higher in calories.

REFERENCES