Video: Do your genes control your weight?

24 June 2018

Obesity is affected by a number of factors such as lifestyle behaviours like a poor diet, high in salt, sugar and saturated fat, sedentary behaviour, and excessive alcohol consumption. Furthermore, genes play a role in contributing to obesity risk.

Some research has shown that certain foods and beverages – like sugary drinks, fried foods and coffee – might interact with genetic susceptibility to overweight and obesity. This has led researchers to investigate the interaction between changes to adherence to healthy dietary patterns over the long term and genetic proneness to obesity or weight gain over time.

Data from two long-term studies were included. The Nurses’ Health Study and Health Professional Follow-Up studies have tracked the health of large groups of female and male health professionals, respectively, over the past few decades.

For this study, weight measures were captured in addition to dietary intake. Diet scores were calculated against a few measures including the AHEI-2010 score, based on 11 foods and nutrients predictive of chronic disease risk, and the DASH score, based on eight foods and nutrients emphasised or de-emphasised in a DASH style diet (Dietary Approaches to Stop Hypertension). Genes associated with body mass index (BMI) were identified and a genetic risk score calculated.

Researchers found regular interactions between differing diet quality scores and genetic predispositions to changes in BMI and body weight over the long term. Increased AHEI-2010 and DASH scores were found to lessen the genetic risk of changes in BMI. The positive effective of improving diet to minimise or prevent weight gain was most pronounced in people at high genetic risk.

Implications

This research suggests that even those at genetic risk of high BMI and body weight can mitigate this through healthy dietary patterns over the life course. While genes play an important role in determining health outcomes, in this case they don’t override a healthy lifestyle, giving people some control over their weight outcomes. Body weight accumulates over time and it can often be more difficult to shed kilos as we get older. It’s important to start adhering to healthy dietary patterns early on in life and stay as consistent as possible throughout life. A healthy diet is one high in fruits and vegetables, fish, nuts and grains, and low in sugar, salt, saturated fats and highly processed foods.  

Last Reviewed: 24 June 2018
© Norman Swan Medical Communications.

References

Wang, T et al. (2018). Improving adherence to healthy dietary patterns, genetic risk, and long term weight gain: gene-diet interaction analysis in two prospective cohort studies. BMJ 360: j5644 doi: 10.1136/bmj.j5644.