As a mechanism to ensure the health and survival of our species, humans crave high-calorie foods over low-calorie foods, especially in times of food scarcity (which is the majority of mankind’s experience on the human timeline). But this attraction to calorie-dense foods is detrimental to health when food is abundant, which is why obesity is a huge health problem in developed countries like the United States, and an emerging crisis in developing countries gaining in affluence. In a small study published in the journal Nutrition and Diabetes, researchers from Tufts University wondered if this food preference could be reversed when the need for high-calorie foods disappeared. In other words, could humans learn to see low-calorie foods as more rewarding than high-calorie foods? Jacque Wilson says the researchers used six months of behavioral modifications and before-and-after MRI’s to prove the plasticity of the mind and the fact that, yes, humans can learn to seek out — even crave — low-calorie (and healthier) foods:

Both groups again underwent an fMRI scan, and researchers showed the study participants photos of low-calorie and high-calorie foods, such as a turkey sandwich on wheat bread and a container of french fries. They looked at how the participants’ brains responded to these photos, particularly in the striatum, a region known to be associated with the brain’s reward system.

Previous studies have shown that high-calorie, fatty, sugary foods trigger the pleasure center of the brain. That’s why you naturally crave these unhealthy foods: You expect to be rewarded with dopamine for eating them.

But people in the experimental group showed a slightly different response to seeing high-calorie foods after participating in the intervention program. Researchers saw less activity in the striatum when participants were shown these foods and more activity when they were shown lower-calorie foods.

The same did not hold true for the control group.


There is a way to train a brain to crave healthier foods before adulthood, and even before childhood. Linda Carroll points to new data, published in this month’s Pediatrics Supplementthat once again shows the benefits of exclusive breastfeeding in the first six months of life:

Breast-feeding in infancy also increased the likelihood that children would be consuming a healthy diet later on. At age 6, children who were breast-fed drank sugary beverages less often and consumed water, fruits and vegetables more often than those who were bottle-fed, CDC researchers found.


All babies — whether breastfed or bottle-fed — seem to have an innate preference for the sweet and savory, rather than the bitter. Therefore, it’s natural for young children to turn their noses up to green vegetables. But there is mounting evidence that breastfed babies are more open to different flavors, and that when a developing fetus and young breastfed infant are exposed to these flavors, they are more likely to prefer them. Parents can continue to mold these preferences towards healthy foods after they are born — even if they are fed formula:

Parents can increase the likelihood that their child will make healthy choices if they start offering fruits and vegetables during late infancy. Researchers found that when children ate fruits and vegetables infrequently during infancy, they continued to eat them infrequently at age 6.


We’ll look at some other benefits related to breastfeeding and the prevention of obesity tomorrow.