Due to differences with sampling methods and time periods, it is rather difficult to directly compare obesity rates in different countries so any numbers mentioned in this article are best-guess estimates.

According to the WHO Global Database on BMI, the small Micronesian island of Nauru has the highest obesity rate (BMI>30) with a massive 78.5% of adults falling into this category. Incidentally, Nauru also has the highest rate of diabetes in the world. Pacific Island nations are over-represented in obesity statistics with the 6 most obese countries coming from this region.

Several studies have found that obese people are much more likely to be deficient in vitamin D compared to the general population.

One study, published in the journal Obesity Surgery, in 1993, found that in a group of 60 morbidly obese females, 62% had 25-hydroxyvitamin D (25-OHD) levels below the normal range of 16-74ng/mL.

While still commonly used in Asian cuisine, legumes have fallen out of favour somewhat in the United States. This is unfortunate because legumes are rich in a variety of minerals, such as molybdenum and folate, that are often lacking in the typical western diet.

Legumes may also have benefits for those looking to lose weight as several studies have drawn a link between diets rich in legumes such as chickpeas, lentils, and beans, and reductions in body weight.

A new study, published in August this year, has found that whey protein, but not soy protein supplementation may aid weight loss and improve body composition.

The study, published in The Journal of Nutrition, involved 90 overweight individuals who were randomly assigned to receive three supplements in addition to their regular diets. The first group received 52g per day of whey protein concentrate, the second group received 52g per day of soy protein isolate, and the third group 52g of carbohydrate in the form of maltodextrin.

One of the concerns of the low-carb diet revolution that has swept the Western world over the last 20 years is that these diets may have a negative effect on long term health. In particular, some health professionals have suggested that individuals who adhere to a low carb diet tend to have higher cholesterol levels and therefore an increased risk of heart disease as a result of higher consumption of fat, particularly saturated fat. Fortunately, most studies have found low-carb diets to have little or no negative impact on cardiovascular health.

Women who eat quickly have a higher average BMI than slower eaters according to the results of a New Zealand study published this month.

The research, led by Dr Caroline Horwath of the Human Nutrition Department at the University of Otago, involved the study of more than 1500 middle aged New Zealand women who were asked to report on their typical eating speed using a 5 point scale ranging from “very slow” to “very fast”.

Choosing foods with a high water content can be a great way to aid weight loss because these foods are very low in calories but still make us feel full. This is due to the fact that water adds volume to foods but contains no calories itself.

A significant amount of data from laboratory and epidemiological studies exists to suggest diets that focus on foods with a low energy density are associated with lower energy intakes, improved diet quality, and long term reductions in body weight compared to other diets.

As a general rule, fruits and vegetables have a very high water content compared to other foods and as a result you can eat large amounts without consuming very many calories at all. For example a cup of strawberries (150g in weight) has just 49 calories, compare that to a slice of white toast with butter (37g in total weight) which has 150 calories. Both result in similar feelings of fullness however the strawberries have just 1/3 the calories.

The following table lists the 20 fruits and vegetables with the highest water content.

Obesity is known to be associated with many potentially life threatening diseases such as heart disease, diabetes, and some forms of cancer. According to most scientific studies, there is an inverse linear relationship between life expectancy and body mass index (BMI). Those who are considered obese (a BMI greater than 30) can expect to live on average 6 to 7 years less than people in the normal weight range (BMI less than 25).

One study, published in the journal Annals of Internal Medicine, looked at the impact obesity has on remaining life expectancy at 40 years of age. The study involved 3,457 individuals who were divided into three groups: normal weight (BMI < 25), overweight (BMI between 25 and 30), and obese (BMI > 30).

According to recent evidence, diets high in fish oil may lower an individual’s body fat levels by increasing the rate of fat oxidization in the body.

One study, published in the International Journal of Obesity in 1997, looked at the effect of high doses of fish oil on total weight, body fat, and the rate of fat oxidization. The research involved six volunteers who were fed a control diet over a three week period followed by a high fish oil diet where 6 g/day of fat was replaced by 6 g/day of fish oil.

A shortage of vitamin C is associated with high body fat levels due to a reduction in the bodies ability to burn stored fat for energy according to the findings of several recent studies.

One such study, published in the Journal of Nutrition in July 2007, looked at the levels of Vitamin C in the blood of a group of 118 middle aged individuals. The researchers found that the heavier individuals tended to have lower levels of vitamin C in the blood. The average vitamin C level of the participants with a BMI lower than 25 was 54.4umol/L compared to just 37.2umol/L for individuals with a BMI greater than 35.