Low-fat, low-carb, pineapple, stone age and mediterranean diet or simply fdh – eat the halfte. Who would like to lose weight, already has the agony of choice in the selection of the diet.
What doesn’t make it any easier: some recent studies indicate that the decision should take into account not only personal preferences, but possibly also the personal genetic profile. According to the study, genetically determined stofechsel characteristics influence how well a person responds to a particular diet. In the worst case, all the efforts were in vain, if the selected diet does not fit the personal profile.
However, this principle still seems to be far from practical implementation: according to a new study by u.S. Scientists, previously taken into account genetic characteristics do not play a role in weight loss success, at least in the comparison between a low-carbohydrate (low-carb) and a low-fat diet. In general, both types of diet help equally well or poorly in losing weight.
The team around christopher gardner from stanford university medical school (u.S. State of california) had divided 609 overweight study participants between the ages of 18 and 50 into two groups. One low-fat, the other low-carbohydrate diet for one year. In the low-fat diet, the consumption of fatty foods such as dairy products, sausage and chocolate is limited. This is how the amount of calorie-rich fat consumed is slowed down – you should lose weight.
In the low-carb diet, carbohydrate-rich foods such as bread, pasta, rice, but also fruit and many types of vegetables are largely taboo. The idea behind it: carbohydrates are converted to glucose in the body, blood sugar levels rise. To counteract this, the body secretes insulin, which transports sugar into the cells. Many carbohydrates lead to a strong insulin release and consequently to a rapid drop in blood sugar levels, which then triggers a feeling of hunger again.
To prevent this, the low-carb diet should include fewer and, above all, high-quality carbohydrates – for example, from wholemeal bread. These are broken down more slowly in the body, the ups and downs of the blood sugar level and the associated hunger attacks are thus prevented.
After a one-month transition phase, the participants followed their respective diet plans for a year. They were not given a fixed maximum number of calories – but were asked to eat a healthy and wholesome diet overall, i.E. To eat as many vegetables as possible and less industrially processed foods, and to cook for themselves. Participants received regular training on these and other topics.
To determine the influence of genetic factors on dietary outcomes, the researchers determined which variant of three different genes the participants possessed before the study began. The respective expression is related to the fat and carbohydrate metabolism, according to previous findings. Finally, they used a glucose tolerance test to determine how well the body can regulate blood glucose levels.
After one year, the participants had lost an average of 5.5 kilograms – in both groups and completely independent of their individual gene type and their insulin level. The range of responses to the diet was high: some participants lost up to 30 kilograms, others gained 15 or 20 kilograms. "This study closes the door on some questions – but opens the door on others," erstautor gardner comments on the findings.
The scientists hope that in further studies they will be able to find an explanation for the rough variability in the individual characteristics. "We have a lot of data that we can now use in subsequent studies."Differences may be found in epigenetics – the conversion of genetic information – or in bacterial colonization.
The study once again shows the complexity of the topic of nutrition and how difficult it is to derive recommendations from individual scientific studies. Last year, after some criticism, the german nutrition society (DGE) adapted its ten rules for a wholesome diet. The recommendation to prefer low-fat dairy products was deleted. The reference to health risks from too many saturated fatty acids has also been removed.
Today, society recommends a general preference for vegetable oils and to watch out for "hidden fats" such as those in sausage and ready-made products. With regard to carbohydrate-containing foods, the DGE recommends preferring the whole-grain variety – for example, whole-grain bread instead of toast.