By Dr Ananya Mandal, MD
There has been an exponential rise in the number of obese individuals especially in developed nations like United States and United Kingdom. Now obesity has become a public health problem in most nations.
Obesity is linked to several long term health conditions, premature death and illness including diabetes, heart disease, stroke, gall bladder disease, fatty liver, arthritis and joint disorders and some cancers.
Obesity and calorie intake
Studies have shown that this rise of obesity among the world population could be attributed to an increase in calorie intake coupled with lack of adequate physical activity.
Results from the analysis of data from the National Health and Nutrition Examination Survey (NHANES) indicate increases in quantity and energy density of foods consumed in the United States from 1976 through 1980 (NHANES II) and 1999 through 2002 (NHANES III).
Studies have shown that in the US per capita calorie intake increased by more than 300 kilocalories (kcal) among the entire population from 1985 through 2002. The numbers have only risen over the past decade.
Food choices of individuals depend of several factors including:-
The food choices affect energy intake and this interacts with the genetic and metabolic factors to finally determine the body weight and composition.
Obesity results from an imbalance between the amount of energy taken in, through eating and drinking, and the amount of energy spent on metabolism and physical activity. In children the energy is also spent in large parts in growth and development.
Studies have shown that over the past four decades, consumption of food eaten away from home has also risen alarmingly. It is well known that eating out may lead to excess calorie intake and increases the risk of obesity because of large portion sizes and increased energy density of foods.
Fast foods fall into this category of food. Fast foods are typically:-
high in calories
high in fat
high in saturated and trans fat
high in sugar
high in simple carbohydrates
high in sodium (salt)
Fast food and BMI
Fast food is associated with higher body mass index, less successful weight-loss maintenance and weight gain.
Fast foods reduce the quality of diet and provide unhealthy choices especially among children and adolescents raising their risk of obesity.
Fast-food consumption costs were nearly $164.8 billion in 2010. This was a 3% rise from 2009.
Fast food and childhood obesity
Fast foods affect children and youth often worse than adults. This is because most of the fast foods are targeted towards children and there is a sustained pattern of eating fast foods and eating out.
Children with a sustained excess energy imbalance intake of approximately 2% result in the development of obesity over time.
A 2% imbalance could mean an excess of only about 30 kilocalories per day. This corresponds to two-thirds of a chocolate cookie, fewer than two French fries or one-fourth of a can of soda.
Eating out is another major contributor to childhood obesity. Studies show that calorie content of out-of-home meals that children consumed was 55% higher than that of in-home meals.
Reviewed by April Cashin-Garbutt, BA Hons (Cantab)