Obesity on the rise, high levels of undernutrition persist in India (GS Paper 2, Health)
Why in news?
- India has seen a steady increase in obesity levels over the last 32 years. At the same time, the prevalence of undernutrition has also remained high in the country.
- As a result, India has become one of the countries with a high “double burden,” according to a new Lancet study.
- The study blamed a lack of access to affordable and nutritious food for the prominence of undernutrition and obesity. While lack of access to food can lead to undernutrition, increased access to processed foods high in fats, salt, and sugar has driven up obesity.
What are the parameters of being obese and underweight?
- According to the World Health Organisation (WHO), obesity is an abnormal or excessive accumulation of fat that poses health risks.
- Adults are considered to be obese, if they have a body mass index (BMI) of 30 kg/m2 or more.
- BMI is a person’s weight in kilograms divided by the square of height in meters, according to the Centers for Disease Control and Prevention.
- School-aged children and adolescents, anyone between the ages of 5 and 19 years are considered obese, if their BMI is two standard deviations more than the mean.
- Underweight is one of the four broad sub-forms of undernutrition. An adult is considered underweight if their BMI is less than 18 kg/m2. School-aged children and adolescents are considered underweight if their BMI is two standard deviations below the mean.
What does the data tell about India?
- Obesity in women has spiked in the past three decades, it increased from 1.2% in 1990 to 9.8% in 2022, according to the study. There were 44 million women living with obesity in 2022.
- Meanwhile, obesity in men increased by 4.9 percentage points during the same period, with 26 million men living with obesity in 2022.
- There has also been a significant increase in childhood obesity. There has been a spike of 3 percentage points in girls and 3.7 percentage points in boys over the 32 years that the study examined.
- In 2022, 3.1% of girls and 3.9% of boys were obese. In other words, while 0.2 million boys and 0.2 million girls were obese in 1990, 7.3 million boys and 5.2 million girls were obese in 2022.
Underweight:
- Despite a significant decline, the prevalence of underweight and thinness continues to be high across genders and age groups.
- The study found that 13.7% of women and 12.5% of men were underweight.
- Thinness in Indian girls was found to be the highest in the world, with a prevalence of 20.3%. It was the second highest in Indian boys, with a prevalence of 21.7%.
How do socio-economic conditions affect obesity and undernutrition?
- While it is affecting more people, there continues to be a rural-urban divide when it comes to obesity.
- An analysis of the NFHS-5 data from last year shows that the prevalence of obesity was 31.7% in urban women and 19% in rural women. It was 28.6% among urban men and 18.8% among rural men.
- Undernutrition persists in extremely remote and rural parts of poorer states where access to any kind of food is low.
- Undernutrition is prevalent in the extremely poor populations in states like Bihar, Jharkhand, or Odisha, where people might be eating just one meal a day.
What are the impacts of obesity and undernutrition?
- The health consequences of obesity are obvious. An increase in obesity, especially in children, is likely to lead to an increase in diseases such as diabetes, hypertension, heart attacks, and strokes. The effect of undernutrition, however, is not so obvious.
- The undernutrition is likely to increase the burden of non-communicable diseases.
What needs to be done?
- Obesity and underweight should not be considered in isolation. Because the underweight-obesity transition can occur rapidly, leaving their combined burden unchanged or higher.
- It proposes that the focus has to be on programmes that enhance healthy nutrition, such as targeted cash transfers, food assistance as subsidies or vouchers for healthy foods, free healthy school meals, and primary care-based nutritional interventions.
- Other than ensuring food security, the study also mentioned that there is an urgent need for supporting weight loss in those with obesity.
- Prevention and management are especially important because the age of onset of obesity has decreased, which increases the duration of exposure. Making healthy food affordable and accessible is the challenge.
Homesexuality is ‘natural’ in the animal kingdom
(GS Paper 3, Science and Technology)
Why in news?
- Homosexuality is not uncommon in the natural kingdom. Its incidence has been reported in “over 1500 animal species” ranging from tiny insects and spiders to reptiles, birds, and mammals.
- It has been observed in both males and females, and in both captivity and the wild.
A Darwinian paradox:
- There is mounting evidence to suggest that biological and genetic factors are major drivers behind homosexual behaviour.
- While there is no one ‘gay gene’, and environmental factors too play a role, a 2019 study in found that five genetic markers to be “significantly associated” with same-sex behaviour in humans. This, however, creates a paradox.
- The very basis of Charles Darwin’s theory of evolution lies in the fact that the goal of all organisms, and thus of evolution itself, is reproduction i.e. the passing down of one’s genes to the next generation.
- Same-sex sexual behaviour does not serve this purpose. Instead, it actually diverts scarce resources and time into activity that actively precludes organisms from reproducing.
The ‘indiscriminate mating’ hypothesis
- There are many hypotheses which try to explain same-sex sexual behaviour in animals. One, which has gotten a lot of attention in recent times, is the “indiscriminate mating” hypothesis.
- According to it, “the ancestral animal species mated indiscriminately with regard to sex if only because it is unlikely that the other traits required to recognize a compatible mate, evolved at exactly the same time as sexual behaviours”.
- The mate recognition can require physiologically and cognitively costly adaptations, and being excessively discriminating in choosing mates can lead individuals to miss out on mating opportunities that lead to reproduction.
- Thus, according to this hypothesis, the present-day diversity in sexual behaviour in animals stems from an ancestral background of indiscriminate mating among individuals of all sexes.
Adaptive functions:
- Other hypotheses, attempt to explain homosexual behaviour in animals in terms of its adaptive functions.
- Evolutionary biologists N W Bailey and M Zuk first hypothesised that “same-sex sexual behaviour contributes to establishing and maintaining positive social relationships”. Consequently, such behaviour is more common in social rather than non-social species.
Link with sociality:
- A 2019 study found evidence for this hypothesis. They wrote that there is a “direct correlation” between the incidence of same-sex sexual relations and sociality, and that it “has been favoured evolutionarily as a way to establish, maintain and strengthen social relationships that may increase bonds and alliance between members of the same group.”
- They also suggested that same-sex sexual behaviour contributed towards “diminishing intrasexual aggression and conflict”.
- Such interactions, they hypothesised, “may serve to communicate social status and establish and reinforce dominance hierarchies, thus preventing future conflicts, or may contribute to diverting aggressive behaviour toward courtship behaviour”.
- Consequently, same-sex sexual interactions should be more common in species with aggressive, often lethal, intrasexual relations.
