Preventing or delaying type 2 diabetes

Unlike type 1 diabetes, type 2 diabetes is, to a large extent, an area where prevention has proven itself — particularly at the prediabetes stage, an intermediate phase that affects more than one in ten adults in France.

A real window for action at the prediabetes stage

Prediabetes doesn't inevitably lead to full-blown diabetes. Large international studies, notably the Diabetes Prevention Program in the United States, have shown that, at this stage, targeted lifestyle changes can significantly delay, and sometimes even prevent, progression to established type 2 diabetes — with a reduction in progression risk of up to 58% in some studies, a result greater than that achieved with preventive medication under the same conditions. This is exactly what makes early screening so valuable: the earlier it's caught, the wider the window for action.

Results confirmed across countries and over time

The American Diabetes Prevention Program, published in 2002 in the New England Journal of Medicine, isn't an isolated case. A year earlier, the Finnish Diabetes Prevention Study (Tuomilehto et al., 2001) had found exactly the same figure: a 58% reduction in diabetes risk among overweight people with prediabetes, through support on diet, physical activity, and weight. In China, the Da Qing study, launched in 1986, followed its participants for thirty years. Six years of lifestyle intervention delayed the onset of diabetes by about four years on average, and reduced cardiovascular events and mortality over the long term (Gong et al., The Lancet Diabetes & Endocrinology, 2019).

The effect fades over time if the changes aren't maintained, but it doesn't disappear. Fifteen years after the Diabetes Prevention Program began, the group that had followed the lifestyle program still had about a 27% reduction in diabetes risk. These programs have inspired public policy: in the United States, the CDC's National Diabetes Prevention Program offers year-long support programs recognized by Medicare; in the United Kingdom, the NHS created an equivalent national program.

More recently, the British DiRECT trial (Lean et al., The Lancet, 2018) went further, working with people who had had diabetes for less than six years. With a structured, supervised weight-loss program, nearly half of participants were in remission a year later, meaning normal blood sugar without medication. The chances of remission rose with weight loss, and lasting remission remains harder to achieve when diabetes has been present longer. This finding shows that the “window for action” doesn't close completely at diagnosis, even though it is wider before it.

The levers that make a difference

• Regular physical activity: at least 150 minutes of moderate activity per week (or 75 minutes of vigorous activity), combined with strength training, directly improves the body's sensitivity to insulin — the very mechanism that fails in type 2 diabetes
• Diet: favoring a balanced, fiber-rich diet while cutting back on fast-digesting sugars and ultra-processed foods, two elements associated with better blood sugar regulation in numerous studies
• Weight management: a modest but lasting weight loss (around 5 to 10% of starting weight) can be enough to significantly reduce the risk of progressing to diabetes in someone who is overweight, a far more achievable target than an ambitious weight-loss goal
• Sleep and stress management, factors sometimes underestimated but which also influence blood sugar regulation, through well-documented hormonal mechanisms (cortisol, the stress hormone, notably has a direct effect on blood sugar)

Screening, the first step before taking action

Before even knowing which levers to prioritize, you first need to know your current risk level. The FINDRISC score, available on Hygietest, lets you estimate this risk from simple criteria — without waiting for symptoms to appear or for a first blood panel — to then guide you, if needed, toward confirmatory blood testing with a healthcare professional.

Screening now built into France's prevention pathways

Since 2024, the “Mon bilan prévention” program has offered adults at key ages (18-25, 45-50, 60-65, and 70-75) a personalized prevention consultation, specifically including diabetes risk assessment — a sign that type 2 diabetes prevention is now fully integrated into French public health policy, not left solely to individual initiative.

What generally doesn't work

In contrast to the effective approaches mentioned above, very restrictive short-term diets generally show disappointing results for long-term diabetes prevention, due to the frequent weight regain once the diet is stopped. Similarly, aiming for radical weight loss right from the start, rather than a gradual, realistic target, is statistically associated with a higher dropout rate — a further argument in favor of a gradual approach rather than an abrupt lifestyle overhaul.

The same applies to dietary supplements marketed as “anti-diabetes” (cinnamon, chromium, berberine, apple cider vinegar...). None has shown a preventive effect comparable to lifestyle changes, and some can interact with medications. They are no substitute for physical activity, a balanced diet, or medical follow-up.

The role of ongoing medical follow-up

Beyond individual lifestyle changes, regular medical follow-up makes it possible to objectively track how risk changes over time, through periodic blood panels, and to adjust the strategy if initial results fall short of expectations. This follow-up isn't meant to induce guilt if progress is slower than expected — its main purpose is to adapt the support provided, possibly bringing in other professionals (a dietitian, an adapted physical activity instructor) if lifestyle changes alone aren't enough to reach the goals set.

A collective dimension not to overlook

Beyond individual effort, several studies highlight the value of social support in successfully making the lifestyle changes aimed at preventing type 2 diabetes — whether through group support, the involvement of close family and friends, or structured programs bringing together several participants who share a similar goal. This finding echoes more broadly what is documented for other lasting behavior changes, where going it alone is often a bigger risk factor for giving up than the intrinsic difficulty of the changes themselves.

What to remember

Type 2 diabetes isn't a disease that appears without warning: signals exist, often well before diagnosis, and concrete actions can genuinely change the trajectory — provided they are identified and acted on early enough, ideally at the prediabetes stage rather than after established diabetes has set in.

To estimate your own risk level, take the “Am I at risk of diabetes?” test.