Do Artificial Sweeteners Make You Fat?
Studies in rats suggest that they may well do so, which might go some way toward explaining the modern rise in childhood obesity. New Scientist reports:-
Susan Swithers and Terry Davidson at Purdue University in West Lafayette, Indiana, gave rats set amounts of yogurt sweetened with either sucrose or saccharin, plus an unrestricted supply of ordinary rat food and water. Five weeks later, the saccharin-fed rats had eaten more food, gained more weight and put on more body fat than the others.
The researchers also found that giving the sucrose-fed rats a high-calorie chocolate pudding treat made them eat less afterwards, whereas the saccharin-trained rats showed less restraint in what they ate next.
The full write-up of the study is here (pdf file, 667kb), and concludes that:-
Animals may use sweet taste to predict the caloric contents of food. Eating sweet noncaloric substances may degrade this predictive relationship, leading to positive energy balance through increased food intake and/or diminished energy expenditure. ... These results suggest that consumption of products containing artificial sweeteners may lead to increased body weight and obesity by interfering with fundamental homeostatic, physiological processes.
It has been clear for a while that weight gain or loss is much more complicated than just how much you eat and exercise. Some years ago I joined a gym which I used for about 3 months - during which time I put on about 1/2 stone (3-4kg) - until I mangled my back. After another three months - of rather cautious lack of exercise - I was back to my old weight again. The reason for the weight change was simply that I came out from a gym session ravenously hungry, so I ate more.
In my rather simplistic way, it seems obvious to me that if you don't want your kids to drink so much sugar in sweet drinks, then you give them drinks which are less sweet - milk, water, even fruit juice. You don't go and stuff them full of even sweeter drinks packed with strange, nasty-tasting chemicals. Looking at my local supermarket's shelves, it seems I am in a minority. You even get 'diet' or 'lo-sugar' versions of drinks marketed as 'healthy', for heaven's sake! Are people really so daft?
The way in which you exercise impact as well. Being hungry afterward is
perfectly normal, and healthy. If your workout involved large amounts of
weight then you may have built muscle, or replaced fat with muscle which
will make you weigh more.
That's the point really - our bodies are designed to match the amount we
eat to the amount we need; yet so much of a modern diet (especially kids'
food) seems to subvert a lot of these mechanisms.
Coincidentally, the BBC reports today that
eating breakfast can help keep your weight down.
This isn't exactly news as such. I learnt about this when I was doing my
GCSE's over ten years ago. It was after that I stopped drinking diet stuff
because artificial sweeteners do make you hungry.
I'm still waiting for them to discover that dairy products are one form of
animal fats that are really good for you. Cream buns are my ideal of the
ultimate healthy snack!
Perhaps people can counteract the effect of artificial sweeteners
(depriving your body of sugar and thus intensifying cravings/hunger which
results in higher food consumption) if they had a balanced diet including
simple sugars from fruits & veggies, and complex sugars found in whole
grains. This way your body IS receiving enough sugar and will not go into
starvation mode. I lost a 100 lbs and found that I achieved less success
the more I deprived myself of certain foods. Artificial sweeteners alone
aren't going to make you fat; a poor diet and lack of exercise will.
Hi Tamara, I agree that the situation is not simple. The human body has a
quite complex balancing mechanism for matching consumption and usage of
food energy. The trouble is that modern diet and lifestyle subvert this
mechanism. Artificial sweeteners break the association between sweet
flavours and increased blood sugar/energy; similarly lack of breakfast
seems to persuade the body to turn down its energy usage.