Diet? It is a matter of arithmetic: a reduced calorie intake and an increased calorie consumption through activity. Easy, if you never tried.
the molecules present in foods can disrupt the system by stimulating or suppressing appetite, by increasing or decreasing the storage.
Cells talk to each other in a complex language of chemical messages. They instruct each other to grow, to move and to respond to threats. Problems in cell communication lead to diseases such as diabetes and cancer. The messages take many forms, including hormones and charged molecules called ions. Cells also listen to signals that come from outside the body.
Understanding the influence of food on cells could offer a better way to design diets, says Seeley. Seeley and his colleague, Karen K. Ryan, argue that food’s effects on the body are so complex and specific that a meal is almost like a cocktail of hormones. Knowing these hormones means being able to elaborate diets either for weight loss or for the treatment of obesity-related diseases, like diabetes and heart disease. A revolution, according to the experts, whose contours are already recognizable. In the 90s, for example, reserchers identified new receptors in the nucleus of cells in our body that can be activated by fatty acids and play an essential role in the energetic balance.
In a nutshell: eating fatty foods not only provides an excess of calories, but modifies the metabolism favoring obesity, changing the "management" of fat in the body.
Scholars have been trying to understand of how food can regulate and influence cells for decades. The public health challenge is translating these specific findings into clear diet recommendations. Current recommendations do jibe with the newer findings: for example, the American Heart Association advises people to eat fish because omega-3 fatty acids have been linked to heart-healthy measures including reduced risk of abnormal heartbeats and slightly lower blood pressure. Fatty acids aren’t the only hormone-like food elements. Amino acids can also activate a chain reaction of events in cells related to cell growth and insulin. Vitamin D and other vitamins are involved with the body’s immune response.
And more interactions could be discovered. Seeley says that in the future, scientists might know which foods promote health by understanding the way the food interacts at the cellular level. Diets could be designed “from the bottom up,” he says.
Bottom line: we should not be "obsessed" by the calorie content of the food if we want that a diet helps us to be healthy: "In the future maybe diets can be very different, depending on how each of us responds to hormone-like substances contained in various foods. Of course today we are sure that a 'right-for-everybody' diet cannot exist," concludes Seeley.
Sources: https://www.sciencemag.org/, http://blogs.scientificamerican.com/