Over the past year, global media has flooded us with news about novel forms of anti-obesity drugs demonstrating dramatic impact on weight reduction and diabetes control while also offering proof of protection against cardiovascular disease.
These drugs (mostly belonging to the class of glucagon-like peptide agonists) have now become blockbusters in high-income countries (HICs), earning billions for the manufacturers.
Patients are clamouring for them, and imitation products are emerging rapidly to exploit the demand-supply gaps.
Low and middle income countries (LMICs) have a different pattern of disordered nutrition. Many of them have several forms of malnutrition co-existing in their populations.
These are:
Undernutrition in children (manifesting as: underweight (for age); stunting (short for age) or wasting (underweight for height)
Anaemia in women and children
Micronutrient deficiencies of vitamins and minerals which can occur at any age
Overweight and obesity in children and adults (some adults can be overweight and malnourished too).
The Dichotomy Between Obesity and Malnutrition Is Complex
Of these, the continuum of overweight and obesity is the most misunderstood, mainly because of long-standing dependence on a faulty measure.
It has been the conventional practice, in the global nutrition community, to use the body mass index (BMI) to pose weight (in kilograms) against height (in metres squared) and use that ratio as the definitive index to separate undernutrition from overweight and obesity.
However, BMI fails to differentiate between the varying contributions to body weight from muscle, fat, bone, and fluid. A muscular body builder may have a high BMI without having high levels of body fat (adiposity).
A person in advanced heart failure or kidney failure may gain weight, not because of high fat or muscle buildup in the body but because of fluid retention.
BMI also does not differentiate between sites of fat deposition. ‘Visceral adiposity’ is a state where fat has mainly accumulated within the abdomen, around the abdominal organs.
This poses an increased threat to health because it is associated with heightened inflammatory activity in the body. That can hurt the heart and blood vessels everywhere.
It increases the risk of hypertension, diabetes, heart attacks, brain stroke, metabolic syndrome, liver dysfunction (metabolic associated steato-hepatitis or MASH), pancreatitis, and cognitive dysfunction.
Since BMI fails to measure visceral adiposity, other measures are used – ratio of waist circumference to hip circumference (WHR) or waist to height ratio (WHtR) which is better and easier to use.
While these types of malnutrition appear definitionally distinct, they can overlap or evolve into one another. A thin person (as defined by BMI) may have a high level of visceral adiposity.
An obese person may be anaemic or zinc deficient. About a third of persons with diabetes in India are noted to be ‘thin’ when BMI is used as the measure.
A high level of visceral adiposity contributes to their metabolic risk, while a low lean muscle mass makes them weigh less.
'Disorded Nutrition Can Be Passed On From Parent to Child'
Transitions in the different states of disordered nutrition can be seen within the life course of an individual, often due to inter-generational effects combining with the impact of current dietary patterns.
When a pregnant woman carries the adverse legacy of her poor nutrition from a disadvantaged childhood and adolescence or is not well fed during pregnancy, the child in the womb is impacted during its growth.
In order to survive, the baby has to preferentially use the limited nutrition that is available for protecting the growth of the brain and the nervous system.
Lean muscle mass shrinks and becomes insulin resistant, so that it does not compete with the brain for scarce nutrients (especially glucose). So, the baby’s body is metabolically programmed to ‘epigenetically’ alter the expression of its genes.
If the foetus in the womb is female, the epigenetic changes can occur in foetal ovaries too, making even the yet-to-be conceived offspring vulnerable in life.
Recent research has shown that paternal obesity too adversely affects the cardio-metabolic profile of offspring conceived through assisted reproductive technology.
What Is the Way Forward?
Our agri-food systems and nutrition programmes must simultaneously address all of these states of disordered nutrition. An age-appropriate diet, which is adequate in calories (energy) and quality assured in its balanced nutrient composition, must be available to every individual throughout the life course.
Defining food security or poverty only in terms of ‘calories consumed by a person’, as some economists have done in the past, will be a mistake.
Dietary diversity and dietary quality matter, both for promoting a healthy nutritional status and for correcting overt and hidden manifestations of disordered nutrition which often co-exist or morph into one another.
For correcting undernutrition in children, we need to identify the right combinations of balanced diets, which are diverse in composition, and appropriate types of physical activity which will build lean muscle mass and strong bones, without bulky banks of abdominal fat.
Dietary quality matters for all nutrition interventions. Plenty of fruit and vegetables, coarse grains and millets, pulses and other protein sources, healthy edible oils, and potable water are essential whichever the form of malnutrition we are trying to avert or correct.
Ultra-processed foods and calorie-dense but nutrient poor beverages can produce many distortions of nutrition and disorders of health. We need to create food systems that can supply healthy foods at affordable cost and regulatory systems that can curb the manufacturing and marketing of unhealthy food products.
By doing so, we will not need to feel ashamed about childhood stunting, alarmed at increasing overweight-obesity or aghast at obese adults trying to procure weight loss drugs at any cost.
(Prof K Srinath Reddy is a Distinguished Professor of Public Health, PHFI. This is an opinion piece and the views expressed above are the author’s own. The Quint neither endorses nor is responsible for the same.)