New research casts doubt on long-held beliefs
Emily Kennedy MSc RHN
Is eating a low-fat diet really the healthiest option? We take a look at the latest research to find out.
Over the past 60 years, the prevalent nutritional advice for heart-healthy living was to follow a diet low in saturated fats—along with lifestyle habits such as plenty of physical activity. This advice was premised on the belief that saturated fats led to a higher risk for heart disease.
The lowdown on low fat
Heart disease is the most talked about condition when it comes to dietary fat. Ever since Dr. Ancel Keys published his Seven Countries Study in the 1950s, both the medical and dietetic industries have promoted a diet low in saturated fat to prevent heart disease.
Instead, the world was seized by a need to go low ... fat, that is. The trouble with this message, it now appears, is that cutting back on fats has meant that many more of us are consuming a much higher rate of carbohydrates in the form of pasta, grains, fruit, and starchy vegetables such as potatoes. Carbs, as we know, break down into glucose.
In addition, turning otherwise healthy foods such as yogurt into low-fat versions meant using fillers—which were usually carbohydrates in disguise, such as fruit purée, fruit juice, dextrin, syrup, or just plain sucrose or glucose-fructose—to add flavour and the texture lost with the fat.
Unfortunately, sugar—in any form—spikes blood sugar, which, in turn, increases insulin. This metabolic cycle sets you up for cravings for more sugar—unless you stabilize with some good fat or protein.
An about-face on saturated fats?
Recent research has inspired doctors and dietitians to discourage single-nutrient messaging, stressing that disease prevention must be holistic.
In light of a landmark study published in the Annals of Internal Medicine in March, the new thinking around heart disease prevention now promotes a balanced, whole food-based dietary pattern that includes all forms of naturally occurring fat—saturated, monounsaturated, and polyunsaturated—in proportion to quality proteins and fibre-rich carbohydrates.
Based on a lack of evidence linking saturated fats to increased heart disease risk, the authors of this study concluded that zeroing in on any one type of fat and labelling it “protective” or “atherogenic” (contributing to lesions or plaques in arteries) may not be the best approach to heart disease prevention.
Instead, the outcome of this review study, involving the pooling and careful analysis of 72 separate studies into the link between fatty acids and coronary disease, was for researchers and medical professionals to call for large-scale clinical trials to review current dietary guidelines.
The associate medical director of the British Heart Foundation, part funder of the study, was quoted as saying, “This analysis of existing data suggests there isn’t enough evidence to say that a diet rich in polyunsaturated fats but low in saturated fats reduces the risk of cardiovascular disease.”
Registered holistic nutritionist and best-selling author Julie Daniluk has always recommended a balanced, whole foods approach that includes all forms of fat for optimal health.
Not only has the link between saturated fats and heart disease come under serious question—according to the newest research—but, according to Daniluk, saturated fats are actually essential for health. Daniluk describes them as the “bricks” providing structure to our cell walls while the mono- and polyunsaturated fats are like the “windows and doors,” facilitating cell-to-cell communication.
Saturated fatty acids, and the cholesterol that often accompanies them, are also key ingredients for production of reproductive hormones.
Cholesterol, adds Daniluk, also serves as a precursor for the biosynthesis of bile acids and vitamin D.
In terms of overall health, a person who isn’t consuming enough fat may experience adrenal fatigue and a slow metabolism due to a low intake of essential fatty acids, according to Daniluk. It’s all about balance and avoidance of personal allergens or systemic toxins.
Vitamin A, essential for good-looking skin, is found in animal sources of fat, such as liver, dairy products, and fish. Vitamin A also needs a bit of fat for absorption so it can be effective in managing acne, psoriasis, and eczema.
According to some experts, dry skin results from a diet that’s too low in fat relative to carbohydrates. Drinking more water will not help revive dry skin if there isn’t sufficient fat to hold it there. A few good oils, such as cold-pressed extra-virgin olive oil or flax oil, drizzled onto salads or into soups, supply the fatty acid building blocks that our oil-producing glands need to help our skin glow with natural moisture.
Make it organic
A strong supporter of organic farming and non-GMO agriculture, Daniluk also urges those who want to eat animal sources of saturated fat to seek meats that are grass fed, as well as free of hormones and antibiotics. This ensures a less inflammatory source of fat (and protein) that will help build your immune system as opposed to attacking it.
Fats to avoid
These fats are the worst kind to consume—they raise “bad” (LDL) cholesterol and lower “good” (HDL) cholesterol. Trans fats are born of oil-hardening hydrogenation, but can also be found in oils that have been partially hydrogenated. These may include corn, safflower, canola, and soybean oils.
Although trans fats were commonly used until recently in many processed baked foods such as crackers, cookies, and cakes as well as fried foods such as doughnuts and french fries, most manufacturers have replaced these harmful fats in their products.
Look for trans fats on the nutrition labels of packaged foods and also check the ingredients list for “partially hydrogenated” vegetable oil.
Fats and their sources
If you want to increase your saturated fat intake, Daniluk suggests it’s a good idea to check the feed of the fat source, if it is an animal source (butter, meat, eggs). Grass-fed versus grain-fed cattle yield significant differences in the fatty acid profile of their meat, milk, and milk products. The same is true for chickens in terms of the vitamin content of their eggs.
Type of fat