Dispelling the Cardiovascular Myth
For decades low fat diets have been recommended to help protect our hearts and curb obesity, but new research is questioning that line of thinking.
Cardiovascular diseases (CVDs) are the number one cause of death in the world. Every year more people die from heart attacks, strokes and congestive heart failure than from any other causes. Estimates suggest there are around 330 million patients in China suffering from CVD, including 245 million of hypertension, 13 million of stroke, and 45.3 million of peripheral artery disease. The traditional recommendation has been to incorporate dietary changes avoiding saturated fat and fat in general.
This has been followed in the West since the 1950’s and since then the number of deaths due to cardiovascular disease have continued to rise. Even though we have been eating less fat, obesity is now at an all time high, it's even considered a global epidemic. In China, obesity rates continue to increase. Two out of five Chinese children and adolescents will be obese in 2030, according to a report issued by Peking University's School of Public Health. So how can we protect ourselves from this global killer?
It is understood that most cardiovascular diseases can be prevented by addressing lifestyle factors. Helpful recommendations include avoiding tobacco use, eating a wholesome diet low in processed foods, achieving a healthy body weight, becoming physically active, and avoiding the excessive use of alcohol. Let us focus on the wholesome diet part. What exactly does “wholesome” mean? Whole foods come from nature and are not processed. We can consider a wholesome diet, one that has an abundance of foods that are as close to their natural state as possible.
Looking back to when fat was blamed for CVD, based on the health recommendations at the time, we switched to a low-fat diet and ended up replacing fats with processed foods and excessive carbohydrates, including simple carbs like sugar. Fats naturally enhance the flavor of food, once removed, sweeteners and other (often) artificial substances must be added to give foods a similar texture or flavor. Now we are starting to understand the harm that excess carbohydrate intake can cause, leading to obesity, fatty liver, and diabetes.
Various meta-analysis and reviews looking at studies from around the world have concluded there is no significant association between dietary Polyunsaturated Fatty Acid (PUFA) or Saturated Fatty Acid (SFA) intake and CVD risk. PUFA’s are found in olive oil, nuts, seeds and fatty fish. The Mediterranean diet, which is high in olive oil, has repeatedly demonstrated to be heart healthy. In our desire to avoid saturated fats (those that are solid at room temperature, and more plentiful in foods like butter), we created hydrogenated oils that have harmful trans fats.
The process of hydrogenation makes oils that are liquid at room temperature, solid. An example of a hydrogenated fat is margarine. Trans fats create inflammation and stiffness in the blood vessels, thus contributing to atherosclerosis, another CVD. It also decreases the amount of HDL in the blood, what we often refer to as the “good” cholesterol. And even more interesting, trans fats contribute to weight gain, specifically abdominal obesity, which is a known risk for CVD.
In line with eating whole foods, some trans fats are found naturally in dairy products, but these are not associated with the harmful effects of man-made trans fats. And if we are talking about unhealthy fats, we must mention ultra-refined seed oils. These undergo treatment to bleach and remove odours; thus, they end up looking very pale, almost transparent in colour. Examples include corn, sunflower and soybean oil.
A point worth noting is that certain studies continue to indicate concerns about saturated fats regarding cardiovascular health. This association might not imply causation; for instance, individuals consuming higher amounts of saturated fats might also be consuming more sugar. The lack of differentiation between the sources or the quality of fats could also contribute to this issue. Additionally, the connection may only be for a portion of the population which seems to experience adverse effects from saturated fats due to genetic factors.
Ultimately, a diet to support cardiovascular health must underscore the importance of real food, nuts, seeds, legumes, a moderate amount of whole grains, good quality sources of protein and an abundance of plants. Natural sources of fat should be incorporated into the diet because fats are needed for hormone production, a healthy brain, nourishing our skin; they give us a steady source of energy and can help maintain balanced blood sugar. Healthy fats include avocados, nuts, olives, and fatty fish. They can also be found in dairy products such as butter, made from cows that consume a grass-fed diet. Interestingly, in multiple studies full-fat dairy products have been linked to lower cardiovascular disease risk.
When it comes to keeping our heart and vessels healthy through the diet, wholesome, natural foods are the answer. Remember fat is not the enemy!
Melissa Rodriguez, N.D.
References
Dietary total fat, fatty acids intake, and risk of cardiovascular disease: a dose-response meta-analysis of cohort studies
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6451787/
Fatty acids: facts vs. fiction
https://econtent.hogrefe.com/doi/full/10.1024/0300-9831/a000713A
Heart-Healthy Diet for Cardiovascular Disease Prevention: Where Are We Now?
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10128075/
Saturated fat: villain and bogeyman in the development of cardiovascular disease?
https://academic.oup.com/eurjpc/article/29/18/2312/6691821
Some 40% of Chinese children face obesity by 2030, study finds
https://asia.nikkei.com/Spotlight/Caixin/Some-40-of-Chinese-children-face-obesity-by-2030-study-finds
Trans-fatty acid blood levels of industrial but not natural origin are associated with cardiovascular risk factors in patients with HFpEF: a secondary analysis of the Aldo-DHF trial
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10584704/
Quality characteristics, chemical composition, and sensory properties of butter from cows on pasture versus indoor feeding systems
https://www.sciencedirect.com/science/article/pii/S0022030216307135