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Study ties Kenya obesity increase to supermarket food


Obesity cases have risen in the last 10 years and are now no longer an urban man’s problem. In the last decade it has become a rural dweller’s concern as well with a thriving retail sector bursting at the seams as supermarkets have cropped up everywhere in that period.

A fresh study now links the two, saying the rapid rise in the number of supermarkets is one of the factors that contribute to unhealthy eating habits that cause obesity.

According to a joint study by German-based University of Göttingen and the International Food Policy Research Institute (IFPRI), there is a “strong” link between modernising of retail sector in Kenya and bad nutritional outcomes such as obesity.

The study titled, Supermarket shopping and nutritional outcomes: a panel data analysis for urban Kenya” was conducted in Central Kenya towns throughout 2017.

It suggests that shopping for food in supermarkets increases adult body mass index (BMI) by 0.64kg/m2. Healthy body weight should have BMI from 18.5 to 24.9 with 25 and above being categorised as overweight, while less than 18.5 is underweight.

According to Kenya Demographic and Health Survey 2014, 47.1 per cent of women in Central Kenya are either obese or overweight. On average, they have a mean BMI of 25.3kg/m2.

Though the Göttingen and IFPRI report does not find that supermarkets contribute to net increases in total calorie consumption, it notes significant shifts in dietary composition showing that the outlets contribute to a sizeable decrease in consumption of energy-giving food in the form of unprocessed staples and fresh fruits and vegetables.

These food groups are hardly sold in the small-town supermarkets in Central Kenya that primarily concentrate on processed foods.

The study links supermarket shopping to significant increase in consumption of dairy, vegetable oil, processed meat products such as sausages and highly processed food such as bread, pasta, snacks, and soft drinks.

It points out that the shifts toward highly processed foods leads to less healthy diets, with higher sugar, fat, and salt contents, and probably lower amounts of micronutrients and dietary fibres.

“These results are alarming from a nutrition and health perspective,” said the report’s lead researcher Kathrin Demmler. “Even though we failed to establish a clear effect of supermarket shopping on the likelihood of being overweight or obese, rising BMI will inevitably aggravate nutrition status in situations where many people are already near or above the BMI threshold of 25kg/m2, as is the case for adults in Central Kenya.”

Overweight and obesity are responsible for various non-communicable diseases that cause high economic costs, human suffering, and low quality of life.

The report, however, cautions that modernising of the retail sector should not be condemned, “because if properly managed it can also have important positive nutrition effects.”

For instance, a recent study in Kenya, showed that smallholder farmers benefit from marketing contracts with supermarkets in terms of higher incomes that also contribute to better quality diets in these farm households.

“It would be wrong to attribute the obesity pandemic in developing countries to the expansion of supermarkets alone. There are many factors that contribute to the nutrition transition. However, the report suggest that supermarkets are not only a symptom of this transition, but they influence dietary habits to a significant extent,” said Dr Demmler.

According to Nielsen, a leading global information and measurement company, shifting consumer trends have driven growth in formal retail, with 30.0 per cent of the Kenyan population now shopping in formal retail establishments compared to 4.0 per cent in Ghana and 2.0 per cent in Cameroon and Nigeria. This is the second highest in Sub-Saharan Africa after South Africa, which has a formal retail penetration of 60.0 per cent.

Generally, supermarkets offer fresh food that is otherwise more difficult to access, especially for lower income consumers living in the so-called ‘‘food desert” neighbourhoods, the study states.

The expansion of supermarkets Kenya and Africa will likely continue, the study concludes, “Hence, from a food policy perspective it is important to understand the diet and nutrition implications and intervene where necessary to avoid undesirable outcomes. Intervening does not imply banning supermarkets.”

It calls for “certain types of regulations” and economic incentives to encourage supermarkets which shun fresh fruits and vegetables because of low profit margins.