Studies have shown that dietary patterns and types are important factors in the occurrence and prevention of cardiovascular disease. The Chinese Guidelines for the Prevention of Cardiovascular Metabolic Diseases with Healthy Lifestyles point out that increasing the intake of vegetables and fruits, and eating fish, eggs, soy products, and dairy products in moderation can help reduce the risk of cardiovascular metabolic diseases. It is also recommended to reduce the intake of salt and oil and limit the intake of sugar and alcohol. In addition, some studies have shown that drinking coffee in moderation may be beneficial for the prevention of cardiovascular disease.
However, a two-sample Mendelian randomization study in the Journal of the American Heart Association suggests that "the number of spoons of cooked vegetables eaten per day", "the number of cups of coffee drunk per day", and "the frequency of adding salt to food" may increase the risk of myocardial infarction, while "total alcohol intake" and "total cheese intake" may help prevent myocardial infarction.
Strategic management of daily eating habits can significantly improve blood lipid profiles, thereby having a substantial impact on the development of cardiovascular disease.
This study used a large-scale genome-wide association study combined with UK Biobank data to explore the association between 9 categories (83 types) of dietary habits and myocardial infarction, and used two-sample Mendelian randomization to evaluate these associations. Multivariate Mendelian randomization and mediation analysis were used to evaluate the mediating role of blood lipids in the effect of diet on myocardial infarction.
The analysis showed that 4 categories (7 types) of dietary habits were causally associated with myocardial infarction, involving coffee, alcohol, grains, and other dietary factors (Figure 1).
Figure 1 Effect of dietary habits on myocardial infarction
Strong evidence showed that "the number of tablespoons of cooked vegetables eaten per day" was the most important risk factor for myocardial infarction (OR=2.17). "The number of cups of coffee consumed per day" (OR=1.33) and "the frequency of adding salt to food" (OR=1.19) were also considered risk factors for myocardial infarction.
In contrast, "total alcohol intake" had a protective effect on the heart (OR=0.682), possibly by increasing high-density lipoprotein cholesterol (4.48% mediating effect) and reducing triglycerides (6.24% mediating effect).
"Number of bowls of cereals consumed per week" was also associated with a reduced risk of myocardial infarction (OR=0.643), possibly by reducing total cholesterol (8.33% mediating effect) (Figure 2). Muesli (consisting of uncooked oatmeal, fruits, and nuts, etc.) (OR=0.523) in cereal foods played a cardioprotective role by increasing high-density lipoprotein (3.69% mediating effect) (Figure 2).
In addition, "total cheese intake" was also associated with a reduced risk of myocardial infarction (OR=0.638).
Figure 2 Potential mediating analysis of the effect of dietary habits on myocardial infarction
Phenolic compounds in vegetables have been shown to have anti-inflammatory, antioxidant, and antiplatelet aggregation properties, thereby reducing the risk of cardiovascular disease. However, raw and cooked vegetables may have different effects. Vegetables may produce toxic compounds and cause nutrient loss during cooking. Food heat treatment processes such as frying and baking can produce toxic substances such as heterocyclic aromatic amines, acrylamide and nitrosamines, especially foods rich in starch and protein, which may increase the risk of myocardial infarction.
Although most studies have shown that drinking coffee in moderation can reduce the risk of coronary heart disease, the caffeine, diterpenes and polyphenols in coffee may increase the risk of hypertension, as well as increase serum cholesterol and homocysteine levels, thereby increasing the risk of cardiovascular disease.
The nine dietary habits involved in the study include: coffee (coffee intake and comparison between different types of coffee), milk (different types of milk and comparison between different types of milk and never drinking milk), alcohol (alcohol intake, monthly drinking of different types of alcohol and comparison between different drinking statuses), meat (pork, lamb, beef, poultry, fish, processed meat intake), cereals (different types of cereals), bread (bread intake, different types of bread and comparison between different types of bread), foods that are never eaten (e.g., never eat sugar vs. do not limit sugar intake), spreadable foods (such as butter, spreads, etc.), others (frequency of adding salt to food, cup of tea per day, number of fresh/dried fruit slices eaten per day, total cheese intake, number of tablespoons of cooked vegetables eaten per day, number of tablespoons of raw vegetables eaten per day, number of cups of water drunk per day, temperature of hot drinks).
