Is food addictive?
Today in age people are getting fatter and fatter. Obesity is now a world wide epidemic. In the USA in 1995 two-thirds of Americans were overweight and obesity was killing 300,000 people a year, sickening millions and costing $99 billion annually. 10 years later and the Americans (the studies I have are from Americans but I bet in Europe it is the same thing) were eating 50 percent more fast food meals and five more pounds of sugar a year. US obesity related health costs have risen to $117 billion!!!(1) So what´s wrong? Why do we keep eating and getting fatter? We know it´s bad for us but we still don´t do anything about it. Are we just plain stupid? Or is there something more complicated that we still don´t understand? Can food be addictive……..
There is growing evidence that sugary foods can trigger changes in the same brain chemicals affected by addictive drugs. Researchers at Princeton have shown that natural opioids are released when rats eat a large amount of sugar and that they are thrown into a state of anxiety when the sugar is removed. Biologist are also finding that overeating on refined fatty meals triggers similar physiological changes. Leptin is a hormone which signals the body to stop eating after a certain point when consuming natural foods (2). Well, researchers at Albert Einstein Medical College saw that when they fed rats unnaturally fatty meals, the rats would loss all of their ability to respond to leptin. They just kept eating!!! The reverse effect happened when they were taken off the high fat for a while. There was also a study at Rockefeller University that showed that a high fat diet reconfigures the body´s hormonal system to want yet more fat. Galanin, a brain peptide that increases eating and slows energy expenditure, rises in rats on a high fat diet (3). In fact, it only takes 1 high fat meal to stimulate galanin release and the craving for fat. So we are beginning to see that food can actually be addictive, but we can also stop this addiction by eating properly. But what is eating properly? Before I answer this question I want to try to clear some terms that I think are important:
- Refined: We always hear this word but few people really know what it means. When ¨refining¨ flour, sugar or other foods, it means it is removing the hull and fiber, often even the cell wall of plant structures, leaving only simple carbohydrate or clear oil. Farming refines our food all the time. A recent study of nutrients in food found that, in the second half of the last century (1900-2000), fruits and vegetables suffered significant decreases in protein, calcium, phosphorus, iron, vitamin B2 and vitamin C.
- Insulin: When we eat simple carbohydrates, glucose levels soar in the bloodstream. In the short term, our bodies release INSULIN to store the glucose as fat. Repeated surges in blood sugar make the pancreas work harder and can contribute to insulin resistance, thereby increasing the risk for type 2 DIABETES, in which blood sugar levels remain elevated, causing damage to our kidneys, eyes and immune system (4).
- Trans Fats- ¨are produced by heating liquid vegetable oils in the presence of catalysts and hydrogen. This gives them a different shape from the original oil or the natural saturated fats found in meat. They don´t fit properly with cell membranes or with enzyme designed to digest fats. Trans fats cause a significant drop in HDL (good) cholesterol and a significant increase in LDL (bad) cholesterol, they make the veins and arteries more rigid, they cause major clogging of arteries and they contribute to the risk of death from heart disease. Because trans fats contain abundant calories without providing the beneficial fats found in natural vegetable oil, they lead to overeating with under nutrition. Trans fats now make up much of the fat in CANDY, COMMERCIAL COOKIES and cakes, and the oils in which FAST_FOOD CHAINS FRY FOOD¨ (*Taken from Waistland by Deirdre Barrett pg 34)
In my next post I will talk about what eating properly is and how we are doing right now the complete opposite. But in the meantime I would love for you guys to take a look at this link. It´s a series BBC did on obesity and it´s called THE MEN WHO MADE US FAT. It consists of 3 parts and each last 55 minutes but it´s very interesting. Here goes the link: http://www.youtube.com/watch?v=E6nGlLUBkOQ.
Barrett D. Waistland, The (R)Evolutionary Science behind Our Weight and Fitness Crisis.Norton & Company.2007
Egan S. Making the Case for Eating Fruit. New York Times. July 2013.
Colantuoni C. Evidence that intermittent, excessive sugar intake causes endogenous opioid dependence.Obesity Research 10,6 (2002):478-88.
Martindale D. Burgers on the Brain:Can you really get addicted to fast food?, ¨New Scientist, February 1,2003.
Wang J. Overfeeding Rapidly Induces Leptin and Insulin Resistance. Diabetes 50(2001):2786-91.