Obesity, exercise and older women

Dr Derrick Aarons

Sunday, August 19, 2018

Print this page Email A Friend!

WHETHER we are slim, medium build, overweight, or severely obese, our current body size is a result of our genetic predisposition (genes given to us by our parents) as well as our lifestyle during childhood, adolescence and adulthood.

Genetic predisposition plays a significant part, but recent research has revealed that even women in their 70s can maintain a healthy weight despite any genetic predisposition to become obese, as long as they are physically active for more than 150 minutes each week.

This modest level of aerobic activity can be achieved by all individuals who are able to walk briskly for around 30 minutes each day over five days. This 30-minute daily exercise can be completed all at one time, or — for the best blood sugar control — the walking exercise can be done for 10 minutes after each meal for a total of 30 minutes each day.

The morbid condition of obesity

Obesity is a condition in which a person's body weight is 20 per cent or higher than what it should be, and for easy measure, a waist circumference of more than 35 inches for women and more than 40 inches for men indicates abdominal obesity. The concern is great worldwide as the number of people with obesity has doubled over the past 30 years, and now over one-in-three individuals (35 per cent) are either overweight or obese.

Overweight and obesity are now the fifth-leading risk for premature death worldwide, with at least 2.8 million people dying each year as a result of being overweight or obese. Further, 44 per cent of diabetes illness, 23 per cent of ischaemic heart disease burden, and between seven and 41 per cent of certain cancers are attributable to individuals being overweight or obese.

Genetic research

In a large genetic study, 8,000 women of European ancestry between the ages of 50 to 80 years old were interviewed in a Women's Health Initiative (WHI) and the findings published online in the May 2018 edition of the journal Menopause. The research was conducted by academics from the School of Public Health and Health Professions at the University at Buffalo, New York, USA.

The WHI programme was funded by the National Heart, Lung, and Blood Institute; the National Institutes of Health, and the US Department of Health and Human Services.

Prior to that, relatively little was known about whether genetic predisposition to obesity could be reduced in older age by healthy behaviours such as physical activity. So, to investigate this, the researchers examined data from 8,206 women participants in the WHI who had an average age of 67.8 years. They developed a genetic risk score that was associated with people's body mass index (BMI). Body mass index is a weight-to-height ratio used as an indicator for overweight and obesity.

The researchers then examined whether the genetic predisposition for obesity was modified by age or by the level of physical activity. People were classified as being sedentary, or having a low, moderate, or high activity level; where moderate activity was about 150 minutes of physical activity each week.

Additional benefits

The association between BMI and the genetic risk score was strongest in sedentary women, and minimal for the most active women. Further, exercise provides additional benefits as people age such as reducing the loss of muscle that comes with ageing, and thereby reducing the risk of falls that may cause fracture of the hip and other debilitating conditions with long- term negative consequences for good health and quality of life.

The study suggested that older people can overcome their destiny for obesity given to them by their parents by engaging in regular exercise. This underscores the importance of promoting and maintaining healthy behaviours as persons age, in order to maximise their quality of life.

Physical activity is crucial

The researchers acknowledge that other factors may explain a part of the findings since it is difficult to separate the effects of age, the dynamics of BMI change in older women, and the exposure to an obesogenic environment across the lifespan of the women. However, their research findings suggest that genetic predisposition to obesity is not wholly deterministic, and that other factors also contribute to the particular outcome of people's weight.

Consequently, physical activity may reduce the influence of any inherited susceptibility to obesity and healthy behaviours are very important, particularly later in life. This research, along with others, thus encourages the development of recommendations for people's lifestyle that are coupled with the use of beneficial genetic information.

Dr Derrick Aarons MD, PhD, is a Jamaican family physician and consultant bioethicist; a specialist in ethical issues in health care, research, and the life sciences; and is the health registrar and head of the health secretariat for the Turks & Caicos Islands.

Now you can read the Jamaica Observer ePaper anytime, anywhere. The Jamaica Observer ePaper is available to you at home or at work, and is the same edition as the printed copy available at




1. We welcome reader comments on the top stories of the day. Some comments may be republished on the website or in the newspaper � email addresses will not be published.

2. Please understand that comments are moderated and it is not always possible to publish all that have been submitted. We will, however, try to publish comments that are representative of all received.

3. We ask that comments are civil and free of libellous or hateful material. Also please stick to the topic under discussion.

4. Please do not write in block capitals since this makes your comment hard to read.

5. Please don't use the comments to advertise. However, our advertising department can be more than accommodating if emailed:

6. If readers wish to report offensive comments, suggest a correction or share a story then please email:

7. Lastly, read our Terms and Conditions and Privacy Policy

comments powered by Disqus



Today's Cartoon

Click image to view full size editorial cartoon