Key points: A March 2017 paper published in the Journal of the American College of Cardiology” by Andrew M. Freeman et al, entitled “Trending Cardiovascular Nutrition Controversies”, reviews current nutrition-based claims and assumptions that are hitting the mainstream media regarding atherosclerotic cardiovascular disease (ASCVD). From the association of eggs and cholesterol to juicing and vegetarian diets for ASCVD this article explains the challenges and current evidence behind different diets and nutritional trends.
There are inherent challenges to studying nutritional science to support patient management. According to the authors, nutrient-based randomized control trials (RCTS) tend to be too short in duration to fully understand the effects of diet interventions. This may be due to the expense and high patient dropout rate. The authors also note that blinding, too, has been an issue for many nutritional interventions making the results more challenging to interpret than pharmaceutical or drug trials. Despite these difficulties, it is undeniable that diet plays a significant role in health and disease and this is also true in ASCVD. ASCVD is associated with high BMI levels, unhealthy cholesterol levels, peripheral artery disease, and inflammation- many of which are responsive to healthy diet and lifestyle changes.
This review looks at all the evidence to determine what is truth or myth regarding the consumption of eggs, nuts, various cooking oils, berries, nutritional supplements, vegetables, juicing, and gluten in ASCVD. It is not fully understood what the ideal diet is for the prevention and maintenance of ASCVD. Assessing the evidence is the best way to know what works, and what doesn’t.
Coconut oil and palm are both high in saturated fatty acids. Evidence suggests these raise cholesterol levels and should be avoided to prevent ASCVD. Although eggs are healthy in small amount, eggs also raise serum cholesterol and should be consumed sparingly. Juicing, if the pulp is removed, concentrates calories and does not appear to have any benefits. Evidence suggests that any diet that promotes high levels of fats, fried food, processed meats, and sugar drinks should also be avoided.
Consuming virgin coconut oil, high dose-antioxidant supplements, and gluten containing foods all do not have sufficient evidence to ascertain if they are beneficial or harmful for ASCVD. Additionally, juicing that includes pulp does not have enough supportive evidence although it appears to be more beneficial than non-pulp juicing.
Evidence has shown the extra virgin olive oil may reduce some CVD concerns, when consumed in a healthy quantity. Three servings per week of blueberries and strawberries are shown to provide protective antioxidants for heart health. Nuts, limited to 30g per serving to avoid weight gain, are also shown to provide healthy fats and benefit CVD outcomes. Both green leafy vegetables and plant-based proteins provide heart healthy and protective effects and have enough evidence to recommend to patients. In fact, plant based proteins are significantly more heart healthy than animal based proteins.
Consuming a diet high in vegetables and healthy fats and low in sugar and processed foods may have significant benefits on a variety of health conditions, including ASCVD. Diets and specific foods, such as the ones outlined above, may have a greater impact on ASCVD development and treatment but more research is needed to fully understand these relationships.
Why is this clinically relevant?
- It is important for clinicians to know what the current evidence is for diet and nutrition for ASCVD; particularly as it relates to media-driven dietary trends
- Evidence shows that diets high in nuts, antioxidant rich foods, vegetables, and healthy oils benefit ASCVD
Additional research is still needed to before low gluten diets, juicing, and supplementation of antioxidants can be made for ASCVD therapy