Obesity’s costs; Is there a solution?

The McKinsey Global Institute reported the worldwide cost of obesity to be 2 trillion dollars annually, or 2.8 percent of global GDP.  Costs from it are approximately the same as from smoking or armed conflicts making it one of the three top global burdens.  Obesity is responsible for about 5 percent of all deaths every year worldwide.  

2.1 billion people - about 30% of the world's population - were overweight or obese creating a "steep economic toll", and the proportion could rise to almost half of the world's population by 2030.  The financial costs of obesity therefore due to illnesses it is causing.

Although the debate on this issue has become polarized and sometimes deeply antagonistic, obesity is a complex, systemic issue. The McKinsey Global Institute report proposes that,

•   Existing evidence indicates that no single intervention is likely to have a significant impact, thus capturing the full potential requires engagement from as many sectors as possible.

•   Education and personal responsibility are critical elements of any program aiming to reduce obesity. They include reducing default portion sizes, changing marketing practices, and restructuring urban and education environments to facilitate physical activities.

The advice usually given to obese individuals who want to loose weight focuses on consuming fewer calories and exercising more. The benefits of Mediterranean diet and of such foods as vegetables, fruits, nuts, fiber and fish, are often also touted.  However, mounting evidence reveals that the most common eating pattern in modern societies of three meals daily, plus snacks, is abnormal from the perspective of human evolution, a group of researchers wrote in an article published in the journal Proceedings of the National Academy of Sciences suggesting that intermittent fasting could have benefits.

Ancient hunter-gatherers often ate only intermittently, and only when they had a successful hunting. This suggests that the ability to function at a high level both physically and mentally during extended periods without food may have been crucial in human evolution, and that the human body may have adapted to perform at its best with intermittent fasting.  Such intermittent fasting could consist of eating 500 calories or less either two days each week, or every other day, or not eating breakfast and lunch several days each week, the researchers said.

Low Carbohydrate & Low Fat Diets the Same for Weight Loss

Many claims in lay media and scientific literature have been made regarding the superiority of a certain diet for inducing weight loss.  Two recent studies one published in the Journal of the American Medical Association and the second in Annals of Internal Medicine found that using either a low-carbohydrate or low-fat diet had the same end result. The best diet is that which works best for the dieter.

http://jama.jamanetwork.com/article.aspx?articleid=1900510

Johnston et al report in JAMA finding from their search of 6 electronic databases based on which they estimated the relative effectiveness of diets to affect weight and body mass index from baseline.  Weight loss and body mass index was determined at 6- and 12-month follow-up.

Among 59 eligible articles reporting 48 unique randomized trials that included 7286 individuals, the largest weight loss was associated with low-carbohydrate diets 8.73 kg at 6-month follow-up and 7.25 kg at 12-month follow-up and low-fat diets 7.99 kg at 6-month follow-up and 7.27 kg at 12-month follow-up. Weight loss differences between individual diets were minimal. For example, the Atkins diet resulted in a 1.71 kg greater weight loss than the Zone diet at 6-month follow-up.

They concluded significant weight loss was observed with both low-carbohydrate or low-fat diet. Weight loss differences between individual named diets were small.

http://annals.org/article.aspx?articleid=1900694

In the study by Bazzano et al published by the Annals of Internal Medicine, the effects of a low-carbohydrate diet compared with a low-fat diet of on body weight and cardiovascular risk factors was determined.

148 men and women without clinical cardiovascular disease and diabetes were placed on a low-carbohydrate (<40 g/d) or low-fat (<30% of daily energy intake from total fat [<7% saturated fat]) diet.

Data on weight, cardiovascular risk factors, and dietary composition were collected at 0, 3, 6, and 12 months.

Sixty participants (82%) in the low-fat group and 59 (79%) in the low-carbohydrate group completed the intervention. At 12 months, participants on the low-carbohydrate diet had greater decreases in weight (mean difference in change, −3.5 kg), fat mass (mean difference in change, −1.5%), ratio of total–high-density lipoprotein (HDL) cholesterol (mean difference in change, −0.44), and triglyceride level (mean difference in change, −0.16 mmol/L) and greater increases in HDL cholesterol level (mean difference in change, 0.18 mmol/L) than those on the low-fat diet.

They concluded low-carbohydrate diet was more effective for weight loss and cardiovascular risk factor reduction than the low-fat diet.

Based on these studies both low-carb and low-fat diets induced weight loss but there was not a sizable differences between the two. Finally, the branding of the diet did not have an impact on weight loss.

Cancers linked to Obesity

Obesity is a major contributor to the development of cancer.  According to the National Cancer Institute obesity is associated with increased risks for cancer of the esophagus, pancreas, colon and rectum, breast (after menopause), endometrium, kidney, thyroid, and gallbladder.

 

NHANES 2007-2008 survey found 68 percent of the U.S. adults age 20 years and older are overweight or obese and 17 percent of children and teens ages 2 to 19, are obese.  According to NCI Surveillance, Epidemiology, and End Results (SEER) data, it is estimated that in 2007 in the United States, about 34,000 new cases of cancer in men (4 percent) and 50,500 in women (7 percent) were due to obesity.

In 2003, Calle et al published in NEJM the results of a study of more than 900,000 healthy adults that were followed for 16 years.  The study authors concluded that excess fat could account for 14% of all deaths from cancer in men and 20% of those in women.

A recent study of 92,834 British women enrolled in a database for cancer screening, Fourkala et al reported in an article published in BMJ Open that women who go up a skirt size every decade between their 20s and their 60s are at increased risk of postmenopausal breast cancer.  They also found that “an increase of one size every 10 years led to a 33 percent rise in the risk of postmenopausal breast cancer, while an increase of two sizes per decade led to a 77 percent rise in risk.

Bhaskaran et al study of 5.2 million adults that was published in Lancet found that 166 955 individuals developed cancer and that body-mass index (BMI) was associated with 17 of 22 cancers.  Although the effects varied substantially by site, increase in BMI was roughly linearly associated with cancers of the uterus, gallbladder, kidney, cervix, and leukemia.  BMI increase was positively associated with liver, colon, ovarian, and postmenopausal breast cancers overall. They estimated inverse associations with prostate and premenopausal breast cancer risk, both overall and in non-smokers. By contrast, for lung and oral cavity cancer, they observed no association in non-smokers.  Assuming causality, 41% of uterine and 10% or more of gallbladder, kidney, liver, and colon cancers could be attributable to excess weight. They conclude that extra weight could contribute to more than 12,000 cases of cancer in the UK population every year.

Related Resources:

Physical Activity and Cancer

Energy balance: Weight and Obesity, PhysicalActivity, Diet

Obesity

A study by Ng et al reports on the prevalence of obesity in countries around the world.  Their research that was supported by Bill and Melinda Gates Foundation and published in Lancet, reviewed more than 1,700 studies covering 188 countries from 1980 to 2013.

The study found more than 2.1 billion individuals worldwide are overweight or obese, up from 857 million in 1980.  Also, obesity was estimated to have caused 3·4 million deaths, 3·9% of years of life lost, and 3·8% of disability-adjusted life-years worldwide in 2010.

They based their analysis on body-mass index (BMI) a measure of weight and height.  Individuals with a BMI of 30 or more are considered obese, while those a BMI of 25 to 29.9 are considered overweight, according to the U.S. National Institutes of Health.

Worldwide, the proportion of adults with a BMI of 25 or greater increased between 1980 and 2013 from 28·8% to 36·9% in men, and from 29·8% to 38·0% in women. In the US, 87 million individuals or 27.2% were obese according to study conducted in 2013 (Gallup). The prevalence of obesity has increased in children and adolescents worldwide.  In 2013, 23·8% of boys and 22·6% of girls were overweight or obese in developed countries, while in developing countries 12·9% of the boys and 13·4% of the girls were overweight or obese. One of the “most troubling” findings of the study is that the percentage of overweight or obese children and teenagers has increased by nearly 50 percent since 1980.   In the US alone, nearly 30 percent of the children and teens are either obese or overweight, up from 19 percent in 1980.

More than half of the world’s 671 million obese people live in the U.S., China, India, Russia, Brazil, Mexico, Egypt, Germany, Pakistan and Indonesia.  During the more than three decades studied, the largest increase in obesity rates were in Egypt, Saudi Arabia, Oman, Honduras and Bahrain for women and New Zealand, Bahrain, Kuwait, Saudi Arabia and the U.S. for men.  In adults, the estimated prevalence of obesity exceeded 50% in men in Tonga and in women in Kuwait, Kiribati, Federated States of Micronesia, Libya, Qatar, Tonga, and Samoa.  Since 2006, the increase in adult obesity in developed countries has slowed down.  

Because obesity can raise the risk of diabetes, osteoarthritis, heart disease and cancer, among other health-threatening conditions, strategies to correct it such increase physical activity, decrease of total caloric intake and selectivity the foods eaten are needed as obesity represents a major global health challenge.

Addendum:  A study based on review of the health records of 65,000 that was published in JAMAPediatrics (9/29/14) suggests infants and young children with repeated exposure to broad-spectrum antibiotics at ages 0-23 months are associated with childhood obesity.