The Science of Why Diets Do Not Work Long-Term
June 21, 2025 · Frisian News
Researchers find that most people regain lost weight within five years because the body actively resists caloric restriction, not because of weak willpower. Biology, not behavior, determines why diets fail.
A 55-year-old accountant in Hamburg lost 30 kilograms on a strict low-carb diet over nine months. Within three years, she had regained 28. Her story matches what happens to 80 percent of people who lose weight through dieting. The weight comes back, and science now explains why her body fought to reclaim every lost gram.
When someone cuts calories, the body does not simply accept the shortage. Instead, it launches a counterattack. Hormones like ghrelin spike, making hunger unbearable. Leptin, the hormone that signals fullness, plummets. The metabolic rate slows. The brain treats caloric restriction like a threat, just as it would treat an actual famine. This is not a flaw in willpower; it is basic mammalian survival wiring that has kept our ancestors alive for millions of years.
Diet companies spend billions telling people that weight gain comes down to personal choice. They sell the myth that anyone can eat less and move more, and the pounds will vanish forever. This story sells products, books, and expensive meal plans. It also destroys self-esteem when people fail, because they blame themselves for biological failure. The truth irritates the weight-loss industry: dieting works for a few weeks or months, then the body wins.
Studies from major universities in the United States and Sweden tracked people for five to ten years after weight loss. Nearly all participants gained weight back, with an average return of 70 percent of lost pounds within five years. The body has a set point, a weight range it actively defends. Drastically cutting calories does not change this set point. The body only resets its target if eating patterns change in small, sustainable ways that feel normal, not punishing.
This does not mean weight loss is impossible. It means the fantasy of rapid transformation through restriction will always fail. People who keep weight off do so by making permanent, modest changes: walking more, eating less processed food, sleeping better, managing stress. These changes feel gradual and unremarkable, which is why no one sells them. The hard fact is that there is no shortcut, no special diet, and no product that beats biology.
In 55-jierrige rekkenmaster yn Hamburch ferlearen yn njoggen moannen 30 kilo op in strikte koolhydraatarme diëte. Binnen trije jier hie sy 28 kilo wer terjochkrige. Har ferhaal komt oerein mei wat barget by 80 persint fan 'e minsken dy't gewicht ferlieze troch diëten. It gewicht komt tebek, en de wittenskip útleit no wêrom har liif elk ferlieken gram probearje woe tebek te winnen.
Wan immen caloryen ferminderet, akseptearret it liif it tekort net gewoon. Yn plak dêrfan start it in tesjinoanfal. Harmonen lykas ghreline stijge, wêrtroch honger ûndrieglik wurdt. Leptine, it harmoan dat fersadiging oanjout, falt steil. De stofomsealing geast stadiger. De harsenen behannele caloriebeheining as in bedriging, krekt as by in echte hongersnoad. Dit is gjin gebrek oan willskrêft; it is basis säugdier survivalinstinkt dat ús foar'in miljoenen jier holpen heft oerlibbe.
Diëtbedriuwen jouwe miljarden út om minsken te fertelle dat gewichtstoename op persoanlike keaze neakkomt. Se ferkôpe it mythe dat elkenien minder ite en mear beweegje kin, en de kilo's sille foar altyd ferdwine. Dit ferhaal ferkôpt produkten, boeken en djoere maaltieplannen. It fernûte ek selsrespekt wannear't minsken mislukke, om't se himsels de skuld jouwe foar biologisk falen. De wierheid irritearret de gewichtsferliesindustry: diëten wurkje wat wiken of moannen, dan wint it liif.
Undersikers fan grutte universiteiten yn 'e Feriene Steaten en Sweden folgen minsken gedurende fiif oant tsien jier nei gewichtsverlies. Hast alle dielnimmers wûnen gewicht tebek, mei in gemiddelde teberkears fan 70 persint fan ferliene kilo's binnen fiif jier. It liif hat in ynstelde punt, in gewichtsbereik dat it aktyf ferdigget. It drastysk ferminderie fan caloryen feroaret dit ynstelde punt net. It liif stelt syn doel allinne opnij yn as eetpatronen op lytse, derftalige wizen feroarje dy't normaal oanfiele, net striidsum.
Dit betsjuttet net dat gewichtsverlies ûnmooglik is. It betsjuttet dat de fantaasje fan flugge transformaasje troch beheinung altyd mislukke sil. Minsken dy't gewicht bewaarje, dochte dit troch permaninte, boskatte feroarings oan te bringen: mear rinne, minder ferwurke iten, better sliepe, stress better beheare. Dizze feroarings fiele geleidlik en opmerklik oan, dêrfoar ferkoopt gjinien se. It harde feit is dat der gjin flugge ferbining, gjin spesjaal diëte en gjin produkt bestiet dat tsjin biologie yn wurket.
Published June 21, 2025 · Frisian News · Ljouwert, Fryslân