The Undefeated Champion: Why Lifeestyle Beats the World's Most Popular Diabetes Drug

For me, diabetes prevention is personal. I have prediabetes. My hemoglobin A1c runs between 5.7-6.0%.

Apparently, I’m in good company.

More than 1 in 3 Americans (97 million people) has prediabetes (reference).

And full blown diabetes?

I keep returning to this graph of the prevalence of type 2 diabetes in the United States and never ceased to be astonished.

Prevalence of type 2 diabetes among individuals 45-84 years of age in Asian subgroups vs other ethnic groups. NH, non-Hispanic; NHPI, Native Hawaiin/Pacific Islander. Data derived from the 2020 US census

More than 10% of the US population (nearly 40 million people) have type 2 diabetes.

• 1 in 4 Latino Americans have it

• 1 in 4 African Americans have it

• 1 in 3 South Asian Americans have it

• 1 in 3 Filipino Americans have it

S o the obvious question becomes:What can an individual actually do to prevent diabetes? Is the answer lifestyle or medications?

Diabetes Prevention Program

In one corner, we have metformin.

The first-line agent and most commonly prescribed medication for diabetes. The undisputed, inexpensive medical favorite for the past 3 decades (GLP-1’s may take the crown soon, but for now it’s still metformin). You just have to take it twice a day and your diabetes goes away. An intimidating opponent.

In the other corner we have lifestyle. Most people don’t have time for him. They say he demands too much.

Here what lifestyle asks:

• 7% sustained weight loss

• 150 minutes/week of physical activity (equivalent to brisk walking)

• A “healthy, low-calorie, low-fat” diet emphasizing:

  • <30% of calories from fat

  • <10% from saturated fat

  • ≥15 g fiber per 1,000 kcal

  • Whole grains, vegetables, fruits, low-fat dairy, and lean proteins

No prolonged fasts. No keto. No extreme exercise.

How did the fight go down?

In 2002, these two fought head to head. Researchers enrolled ~3200 individuals with pre-diabetes age >25 and a BMI >24.

They were randomized into one of 3 groups:

1. Metformin

2. Lifestyle changes (see above)

3. Placebo

The results?

It was a 3 year battle with victories by both sides. Both interventions worked.

Lifestyle worked better.

• Lifestyle: 58% reduction in diabetes incidence

• Metformin: 31% reduction in diabetes incidence

And this was with lifestyle fighting with one hand tied behind its back.

Only a third of patients in the lifestyle group were able to reach their target weight at the most recent visit. Only about half reached their target of physical activity at the most recent visit. If lifestyle adherence had been better, the results would have been even more impressive.

We know this because the Finnish applied the DPP lifestyle intervention in their own RCT of ~500 patients (reference). About 250 patients were randomized to the lifestyle group and 49 had very high adherence to it. Zero developed diabetes over 7 years of follow-up in the group that adhered to the lifestyle changes.

Let that sink in: lifestyle was undefeated against diabetes in the Finnish study.

Did these changes last? At 15 years of follow-up, the reductions in diabetes incidence persisted. Lifestyle remained the winner:

• Lifestyle: 27% reduction

• Metformin: 18% reduction

  
  

My take away

If you have prediabetes and want to know what lifestyle changes help, here are my recommendations:

Stage 1: The foundation

• Start with optimizing sleep. If you are sleep deprived, it’s hard to make good decisions about food and exercise

• Begin 30 minutes of continuous low intensity physical activity (i.e., brisk walking) 5 days of the week

• Add fiber. Women should eat 20-25 grams of fiber daily and men 30-35 grams. Fiber has many benefits, including slowing glucose absorption and contributing to the production of short chain fatty acids in your gut, like butyrate, which help with insulin sensitivity

• Avoid drinking sugar containing beverages. These are absorbed quickly, causing a glucose spike. It’s also easy to overdo calories when you drink them.

Stage 2: Ramp up

• If you are a man with a waist circumference (WC) > 40 inches or a woman with WC > 35 inches, consider weight loss. Aim for a small deficit of 150-300 calories per day. Side note: for Asians, your waist circumference should be <35.4 inches for a man and <31.5 inches for a woman; see my post on visceral fat and Asians.

• Add strength training 2 days a week with full body workouts. 3 days is even better. This will build muscle which helps maintain your caloric deficit by preventing your metabolism from slowing down. Building muscle isn’t just about aesthetics—it’s about giving glucose somewhere to go. Skeletal muscle is responsible for roughly 80% of post-meal glucose disposal.

• Get enough protein. The optimal amount of protein is hotly debated, but if you are aiming for a caloric deficit and losing weight, eating enough protein will preserve muscle and help with satiety. I would suggest at least 1 gram/kg of bodyweight or more. For most people, this means 80-120 grams of protein daily.

• Limit alcohol. Alcohol can increase insulin resistance and negatively impact sleep. The medical profession no longer considers any level of alcohol intake to have health benefits.

Stage 3: Extra tips

• Pre-game your carbs. Eat a few bites of protein, or fiber before the carbs.

• Eat yesterday’s rice today. Cooling down rice, potato, or pasta in the fridge creates resistant starch. When you reheat and eat the next day, your blood glucose doesn’t spike as high.

• Walk for 10 minutes immediately after one of your meals. When your muscles contract, they can take up glucose using an amazing GLUT4 transporter that works independently of insulin.

• Wear an over-the counter continuous glucose monitor (CGM) and learn how your body responds to certain foods. Some people spike with bananas (me) and some people don’t. Simply monitoring can change behavior. It’s harder to eat a cookie when you are wearing a CGM.

• Consider a 12 hour eating window and 12 hour fasting window. For example, eat from 7am - 7pm. Then rests your pancreas for 12 hours overnight, cuts down on late night snacking, and helps with sleep. If your body can handle this, consider increasing the fasting window.

  
  

Bottom line

Lifestyle is the foundation.

Medications are useful tools—often necessary ones.

Genetics matter. Biology matters. Life circumstances matter.

There is no moral failure in needing medication.And no guarantee that lifestyle alone will always be enough.

If you skip lifestyle and jump straight to medication, you start from a weaker position.

If you build lifestyle first, medications can work better and at lower doses.

The real winner isn’t lifestyle or medication.

The real winner is the person who understands that diabetes prevention isn’t about perfection. It’s about stacking small, sustainable advantages over time.

Walk most days.

Pay attention to fiber at every meal.

Prioritize sleep.Lift something heavy.

Lose a little weight if you need to.

Do that consistently and you dramatically shift the odds in your favor.

This research shows us that diabetes prevention is both possible and sustainable.The most powerful tools are still the simplest ones—waiting for us in our kitchens and our walking shoes.