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.