The whole world is getting fatter. Some 30% of the world's population is now overweight or obese, raising their risk of health problems. According to a study published by open access journal PLOS One, obesity is rising rapidly in parts of sub-Saharan Africa. According to the World Health Organisation, about a quarter of adult Nigerians are overweight or obese.
The study finds that western influences on diet and lifestyle are playing a part in what looks set to be a serious epidemic.
Weight gain and obesity is generally caused by consuming more calories, particularly those in fatty and sugary foods, than is burnt off through physical activity. The excess energy is stored by the body as fat.
Obesity is an increasingly common problem because for many people in sub-Saharan Africa are adopting a lifestyle more commonly found in the west that involves eating excessive amounts of cheap high-calorie food and spending a lot of time sitting down at desks, on sofas or in cars.
There are also some underlying health conditions that can occasionally contribute to weight gain, such as an under-active thyroid gland (hypothyroidism), although these types of conditions do not usually cause weight problems if they're effectively controlled with medicines.
The growing obesity rates left unchecked are going to create all the health issues and the health systems of sub-Saharan Africa are going to be a lot less able to cope. Besides causing obvious physical changes, it can lead to a number of serious and potentially life-threatening conditions including:
- type 2 diabetes
- coronary heart disease
- some types of cancer, such as breast cancer and bowel cancer
- and stroke
There is also a clear link between obesity and complications from the current coronavirus pandemic, with a few studies showing that being overweight puts people at greater risk of severe complications and death from Covid-19.
Obesity can also affect a person's quality of life and lead to psychological problems, such as depression and low self-esteem.
While the prevalence of obesity has increased among both sexes, women appear to be much more affected than men, which the authors of the PLOS One study think may be down to the amount of physical work men still do.
This causes an additional strain for the health system in Nigeria, which has one of the highest maternal mortality rates in the world. There is evidence that maternal obesity increases the risk of a number of pregnancy complications, including pre-eclampsia (high blood pressure during pregnancy and after labour), gestational diabetes mellitus (GDM), and cesarean delivery.
Excessive weight gain during pregnancy and postpartum retention of pregnancy weight gain are significant risk factors for later obesity in women. Additionally, maternal health can have a significant impact on the in utero environment and, thus, on fetal development and the health of the child later in life.
Data from the Demographic and Health Survey (DHS) Program found that nearly a third of Nigerian women were either overweight or obese in 2018.
This was up from the figure registered in 2013, when about just under a quarter of them (24.7%) were considered overweight or obese. There has been a very noticeable trend in the upward trajectory for the percentage of women considered obese or overweight over the last fifteen years preceding the 2018 survey.
Weight goes with wealth in Nigeria today. The women in the wealthiest household (46%) are five times more likely to be overweight or obese than those in the lowest income bracket (9%). In many parts of Nigeria, there is a cultural element to this - richer and more successful women are often expected to be fatter. But part of this is also due to the pursuit of a lifestyle of people in the affluent nations of the world like the US and the UK.
Education and social status also increase women's chances of putting on more weight than is good for their health, with women who have more than a secondary school education (49%) more likely to be overweight than uneducated women (16%).
Age seems to be another determinant when iT comes to the weight of women, with women in their forties (42%) five times more likely to overweight or obese than women in their late teenage years (8%).
When it comes to the geographical distribution, women resident in the south of the country are more likely to be overweight or obese that those resident in the north. Women resident in the South South geopolitical zone, which had the highest rate of overweight or obese women (43%), were almost three times more likely than women in the North East (15%) to be overweight or obese.
A state by state comparison shows states like Anambra (52%), Lagos (49%), Rivers (47%), Delta (44%), Imo (43%) and Akwa Ibom (42%) have female populations where nearly half of which are either overweight or obese. These states also happen to be among the largest sub-economies in the country.
The worry is that Nigeria, like many Sub-Saharan African countries, is facing a double edge public health challenge with a rising number of overweight adults, who now outnumber large segments of the population who also face problems associated with under nutrition. This dual burden will mean combating both malnutrition and the risks associated with obesity, such as cardiovascular disease, which will prove to major test for its health system.