As new research questions conventional wisdom on the role of cholesterol in cardiovascular diseases, India may need to tweak her nutrition policy to make fresh dietary recommendations.
More than a quarter of all deaths in India in 2015 were caused by cardiovascular diseases (CVD), accounting for more than 2.1 million lives. That makes for more than a fifth of global CVD mortality and contributes majorly to the world’s burden of 17.7 million deaths due to non-communicable diseases every year1. CVDs develop a decade earlier in India as compared to high-income countries. The United Nation’s Sustainable Development Goals call for one-third reduction of mortality and morbidity from CVDs by 2030.
India’s current dietary recommendations
The National Institution of Nutrition (NIN) in Hyderabad issues India’s dietary guidelines. In the latest guidelines (2011), it made some generic statements about cholesterol2. While stating that dietary cholesterol increases blood cholesterol, it recommended three eggs per week, and pegged weekly consumption at less than 200 mg. One large egg contains roughly 180 mg of cholesterol, all of it in its yolk. Some quick maths easily point to the discrepancy in this recommendation. The recommendations do well to state that trans-fatty acids found in vanaspati (hydrogenated vegetable oil) are harmful and should be restricted to 1% of energy intake.
The National Nutrition Strategy 2017, released by India’s planning body NITI Aayog, focuses mainly on eradication of malnutrition and undernutrition. It also envisages better maternal care, and prevention and management of neonatal and childhood illnesses. While the report rightly identifies the double burden posed by the fact that the number of children below 5 years of age suffering from obesity is fast approaching the number which suffers from malnutrition, it does not delineate a strategy to deal with this challenge3.
The Eat Right India mission of the Food Safety and Standards Authority of India (FSSAI) launched in August 2018 rightly focuses on reduction of salt, sugar and fat in diet. But its recommendations are merely generic and based on data from the Indian Council of Medical Research (ICMR) and NIN. It also remains silent on cholesterol and recommends reduction of trans-fat and use of low fat dairy products.
Need for policy update
The challenge to find the ideal nutrition, which prevents diseases and helps maintain health, has been compounded by multinational fat and sugar companies, many of whom fund nutrition studies, advocacy groups and research tailored to suit the industry’s interest. The policy on cholesterol needs to be evidence-based, with the selection of evidence playing a crucial role.
For India’s vast geography and diverse food patterns, one size may not fit all. For instance, the traditional consumption of oil varies vastly from north to south and from east to west in India. Coconut oil, groundnut oil, mustard oil – each has a different composition and effect on the human body. It is thus important to decentralise research and come up with more local and region-specific dietary recommendations. Also, the role of genetics in CVD and nutrition needs consideration.
As the variety of oils on supermarket shelves grows and companies advertise them aggressively, it is important that public awareness programmes rely on scientific evidence to help people make the right choices. This, coupled with increased surveillance and monitoring of cardiac health, will go a long way in addressing India’s CVD problem.
The cholesterol-CVD link
A study covering 18 countries across five continents explored the association of fats and carbohydrate with CVDs and mortality4. It concluded that total body fat and the types of fat were not associated with CVD. Interestingly, saturated fat traditionally been linked with heart attack and stroke, was found to prevent those conditions. The study found a strong association of high carbohydrate intake with total global mortality and called for a reconsideration of dietary guidelines.
While there is overall consensus on the role of trans-fats in CVDs, the role of saturated fat has swung from one research to the next. An important systematic review5 and meta-analysis of large studies recently found no robust association of saturated fats with the total number of deaths due to CVD, coronary heart disease (CHD) ischemic stroke or diabetes in healthy individuals. Another meta-analysis6 concluded that the effect of dietary cholesterol on CVD and serum cholesterol is unclear and that higher intake of cholesterol was not associated with increased risk of CVD.
Heart attack was recognised as a clinical condition merely a century ago with cholesterol first being identified in 1910 from atherosclerotic plaque or arterial deposits. Low density lipoprotein (LDL), commonly known as bad cholesterol was first implicated in 1955 as a risk factor for CVD. With the role of high dietary fat established in increasing LDL levels, cholesterol has become synonymous with the risk for CVD. While these findings led to a focus on recommendations around the fat content in our diets, CVD has reached epidemic proportions in the last six decades.
Following Ancel Keys famous long-term, multi-cultural Seven Countries Study investigating diet, lifestyle and other risk factors for CVD, the US Dietary Guidelines for Americans recommended in 1980 that fat should be restricted to 30% of total calorie intake and saturated fat to less than 10%. However, a low-carbohydrate diet was the standard management tool for diabetes and obesity until mid-1950. It was only after Keys’ study, which classified – rather erroneously – food items like cakes and biscuits as saturated fat and not carbohydrate, that recommendations for carbohydrate rich and fat poor diets were made. This ‘replacement nutrient’ carbohydrate, and the deluge of refined sugar that spike calories in our average diets, is now being implicated for an increased risk of CVD.
Nutrition, at nearly 100 years of age, is a relatively younger field of science. As global markets open up and a large variety of food is available aplenty, people are spoilt for choice. India’s national nutrition policy, which has largely been simple and reductionist, needs to take cognizance of these changing dynamics and evolve multifaceted strategies.
To be on top of the latest findings on cholesterol or any other nutrient, more mechanistic studies and clinical trials exploring various effects of the nutrients (or multiple surrogate endpoints) need to be conducted. These efforts also need to account for modern agricultural practices and their long term impact on health. To fight the double scourge of non-communicable diseases and malnutrition, and to meet the UN Sustainable Development Goal of reduction of CVD, India would do well to engage in such research in nutrition.
[Sambit Dash is a senior grade lecturer at the Department of Biochemistry in Melaka Manipal Medical College, Manipal Academy of Higher Education, Manipal, Karnataka.]