In the past 20 years we US citizens have gained a lot of weight. In 2007, 74% of us (adults) were overweight or obese. In children and adolescents, about 25% are overweight or obese, a tripling of the rate of 20 years ago. The speed of this development is alarming, and has many reasons - less time spent on physical activity, more TV & computer games, more cheap fast food, less available produce in inner cities, and the neglect of home cooking by busy people.
Sugars: Another reason for our weight gain relates to the sugars found in processed foods, from breakfast cereals to donuts, cookies, cakes, jam, candy, energy bars, deserts, soft drinks, etc. In 1900 the average yearly consumption of sugar was 5 lbs, and now it is 135 lbs per person! Sucrose – the sugar that comes from sugar cane and sugar beets, is a 50-50 mix of glucose and fructose. Glucose, derived from food, is the main sugar that circulates in our bodies, fueling our brains, muscles and body processes. Fructose is the main sugar in tree fruits, berries and melons. When fruits are eaten, fructose contributes to their good taste and to our health, because of the many other nutrients in these foods.
High fructose corn syrup (HFCS), however, is another story. Between 1970 and 1990, the consumption of HFCS increased 1000% in the US! It is a mixture of 55% fructose and 45% glucose, and is manufactured from corn. HFCS has been used in soft drinks because of it is 40% cheaper than cane sugar. Animal studies indicate that it contributes to greater weight gain, cardiac risk factors and non-alcoholic liver disease when compared to sucrose. A recent study from UCLA showed that pancreatic cancer cells grew more rapidly in the presence of fructose. HFCS is also implicated in high blood pressure. Researchers at the University of Colorado used survey data on 4,500 adults, and found that people said they consumed about 4 soft drinks a day, imbibing 74 grams of fructose. The more fructose they had in their diet, the more likely they were to have high blood pressure, even when adjustments were made for other factors causing hypertension, such as obesity, salt, or alcohol.
Public recognition of problems with HFCS has led some companies, such as Starbucks, to eliminate it from bakery products; some soft drink makers, such as Gatorade, have cut back on its use. Food companies such as Cargill and Archer Daniels Midland insist that the product is similar to ordinary sugar, and are trying to rename it ‘corn sugar’. Nutrition expert Michael Jacobson, director of Center for Science in the Public Interest, and founder of the Nutrition Action Health Letter, takes a somewhat similar stand by saying that the main issue is that people need to consume less sugar – “Soda pop sweetened with sugar is every bit as conducive to obesity as soda pop sweetened with high fructose corn syrup.”
What to tell ourselves about sugar:
1) As a species, we like the taste of sweet foods, and have receptors for them in our mouths. We evolved eating tree fruits and berries. This pattern will keep us healthy.
2) Refined sugar from cane and beets is all right for special occasions, but there are caveats, as follows …
3) Sugar beets make up about 50% of US sugar, and are mainly genetically engineered (Roundup Ready). ‘Superweeds’ are evolving to Roundup, so that more pesticides may be needed. There is currently a temporary ban on GE sugar beet planting in the US because of environmental concerns. Genetically modified cane sugar research is underway in Brazil, Argentina and India; vast amounts of land has been cleared in these countries to grow sugar. If we did not eat as much sugar, the land could be used for real food, or revert to forest. You can find organic cane sugar, which is not genetically modified, but it is more expensive, and much less likely to be used in processed foods.
4) All refined sugars except for xylitol , mannitol, sorbitol and maltitol contribute to tooth decay and tooth loss, which is a big problem, especially among uninsured, low-income children and adults.
5) Refined sugars are empty calories, and are usually combined in foods with other empty calories, such as refined flour and fat. These foods contribute to obesity, diabetes, and many other serious health problems, as mentioned in this article.
6) Sugar-laden foods displace natural foods such as fruits, vegetables, whole grains and protein in our diets. You can train yourself to satisfy your sweet cravings with tangerines, bananas, dried figs and dates – it takes time and persistence, but your body will be happy for your choices. Be sure to fill up on healthy foods, including protein, before you encounter sweets.
Sadja Greenwood, MD, MPH Back issues on this blog