Researchers looking at novel ways to try to reduce obesity have stumbled upon inulin. More on that in a moment.
Obesity in the US has been increasing for years. As of 2010, more than one-third of US adults (34.9%) are obese.
Obesity-related conditions include things like heart disease, stroke and type 2 diabetes, among others. Some are leading causes of preventable death (meaning, it’s a risk you can do something about). Medical care related to obesity costs almost $150 billion/year.
Dieting and exercise can cause weight loss, but many people can’t seem to follow a plan that involves changing eating habits for any length of time. Others stop, or never start, regular exercise. Some try medications, fasts, cleanses, purging. Weight-loss surgery is another option. Others may try illegal drugs. Often, these methods don’t work for a large number of people. Investigators have been looking for ways to enhance weight loss for decades.
These researchers may have come across a method that will allow safe weight loss through a form of appetite suppression using, not a drug, but carbohydrates. And not just any carbohydrates, but fermentable carbohydrates.
The researchers used mice in their experiments. They fed the mice high-fat diets. One group were given a high-fat diet supplemented with cellulose. Cellulose is a poorly-fermentable carbohydrate found in plant cell walls (“fiber”). The other mice were also given a high-fat diet, and the carbohydrate that they were given was inulin (found in a number of different plants like wheat, chicory and several others). Inulin is fermentable. The bacteria in the gut can use inulin to ale different compounds. Some of the compounds made from inulin were short-chain fatty acid acetate. The mice fed the inulin-containing diet ate less food and gained less weight than the mice fed cellulose.
Next the experimenters wanted to see if acetate alone, injected into the mice would produce the same results. It did.
To see what was happening biochemically, they scanned mouse brains after the mice were injected with radioactive acetate (acetate is a chemical that is normally made in the body). Some of the acetate concentrated in the hypothalamus of the brain, in a specific area called the arcuate nucleus. Some of the radioactive carbon from the labeled acetate was found in some neurotransmitters and small neuropeptides (small protein-like molecules) in the same area of the brain.
The investigators think that the acetate (or byproducts of the acetate) in the brain acts as a kind of anorexic chemical. That is, it somehow signals the brain that the animal no longer needs to eat, temporarily. Therefore less food gets consumed and less weight is gained.
This is an interesting approach, using compounds normally found in some foods to help control appetite, rather than using a drug that is synthesized from chemicals.
There is still a lot of research that needs to be done to see if this also happens in humans, if it’s safe to use in humans, how much inulin needs to be consumed, etc. If that future research shows that it does work, inulin or acetate might be a useful adjunct to help with weight loss.
But for now, it’s still good advice to stick to diet and exercise. (Read more about this study here.)