This question is no joke for anyone who is struggling to change his or her body fat. It is a painful question. I have worked with many individuals and I have had personal struggles in trying to maintain a healthy body-fat level.

Reading the letters from the many readers who wrote into the Health section's 'Lose the weight and keep it off' challenge was painful. All the letter writers have made valiant attempts to change their weight status which they did not bargain for but they have only seen limited success. What is the evidence that continues to make life a living hell for so many people trying to change body-fat level? Can anything meaningful be done about it?

I will share the evidence I have from a nutritional and health-related point of view. I will also discuss our shared responsibility as individuals to achieve our just success.

Genetics

Some people have the predisposition to be fat. Many explanations have been given for this including the thrifty gene theory which is now being disputed by some researchers. This theory suggests that hunter gatherers, especially childbearing women, developed the ability to store excess fat for times of limited food which came in cycles. This potential has led to obesity and its related diseases now in an age when there is no prolonged period of scarcity. This gene is said to be present in Native Americans, people from sub-Saharan Africa and Pacific Islanders.

The somatotypebody typing

There are three basic body types or shapes:

1. The endomorph is the body type which tends to carry more fat in proportion to muscle with small bone structure. These people find it difficult to reduce body fat and increase muscle mass.

2. The mesomorph is more muscular and strong looking and has smaller amounts of body fat.

3. The ectomorph is slim and lanky and has small amounts of muscle and fat mass.

Very few persons are extremes of these body types; people usually have a mix while leaning towards one type.

Caloric intake

Studies have shown that malnutrition in the womb and low-birth weight can lead to obesity in adult life. The increased availability of calories, especially of fats and sweeteners, in recent decades has kept pace with the increase in the body fat of the populations in Western countries.

Stress

Studies have linked increased stress to obesity. One of the hormones which is produced in response to stress is cortisol. Increased cortisol production is associated with insulin resistance and central obesity.

The environment

Another modern reason for our fatness is what is called our obesogenic environment. Mechanisation and automation have impacted our activity level. The design, planning and zoning of our built environment have exacerbated this problem. Community roads are built without sidewalks and bicycle trails, housing developments are approved without green areas and parks for families, unlit streets are the norm in many communities and there is just generally an environment which is unfriendly to physical activity.

The same unfriendly conditions exist for both private- and public-sector workplaces. These environments are filled with strategically placed fast-food stores and there is limited access to healthy food options in schools, workplaces and the wider communities.

Excess energy

The equation seems simple - excess energy intake and limited energy expenditure result in obesity, but what are the factors which drive one person to consume excess energy and to expend too little? Are these factors modifiable? Can changes be sustainable or are we doomed to frustration?

In the next edition of 'Lose the weight and keep it off' on March 25, this column will look at ways, from a nutrition point of view, of fighting back and we will doing it with real people.

Rosalee M. Brown is a registered dietitian/nutritionist who operates Integrated Nutrition and Health Services; email: yourhealth@gleanerjm.com.