Blood Sugar Management

Why blood sugar matters for healthspan and longevity

Blood sugar isn't just a concern for diabetics. The way your body handles glucose after meals affects inflammation, cardiovascular risk, cognitive function, and how fast you age at a cellular level. When blood sugar stays chronically elevated, excess glucose binds to proteins in a process called glycation, forming advanced glycation end products (AGEs). These AGEs accumulate in tissues over time, damaging blood vessels, stiffening collagen, and accelerating the biological aging process ^[1].

Even in people without diabetes, glycemic variability — the size and frequency of glucose spikes and dips throughout the day — is emerging as an independent risk factor. A 2022 study found that glycemic variability indices increase significantly with age, suggesting that glucose instability isn't just a symptom of metabolic disease but may contribute to aging itself ^[2]. Post-meal glucose spikes above 140 mg/dL trigger oxidative stress and endothelial dysfunction, even when fasting glucose looks normal ^[3].

What drives blood sugar dysregulation

Insulin resistance is the central problem. When cells stop responding efficiently to insulin, the pancreas compensates by producing more, which works for a while but gradually fails. The result is a slow drift from optimal glucose handling toward prediabetes and eventually type 2 diabetes. This process can take 10-15 years, during which standard blood tests (fasting glucose, HbA1c) may look "normal" while metabolic damage accumulates below the surface.

The main drivers of insulin resistance are excess visceral fat, chronic physical inactivity, poor sleep quality, and diets high in refined carbohydrates and ultra-processed foods. Chronic stress elevates cortisol, which directly raises blood sugar and promotes insulin resistance. Genetics play a role too — some people develop insulin resistance at lower body fat levels than others.

Practical strategies that work

Meal composition has the largest immediate impact on blood sugar responses. Eating protein, fat, or fiber before carbohydrates in a meal can reduce the glucose spike by 30-40%, a concept sometimes called "food sequencing" or the "glucose hack." A systematic review confirmed that low glycemic index diets significantly improve HbA1c and fasting blood glucose compared to high glycemic index diets ^[4].

Exercise is the other powerful lever. Both resistance training and aerobic exercise improve insulin sensitivity through independent mechanisms. A 2025 network meta-analysis of nine different exercise types found that cycling, resistance training, and combined training all significantly reduced fasting glucose and insulin resistance markers ^[5]. Even a 15-minute walk after meals measurably blunts the postprandial glucose spike.

Sleep deprivation wrecks glucose regulation surprisingly fast. Just four nights of restricted sleep (4-5 hours) can reduce insulin sensitivity by 25-30%. Prioritizing 7-8 hours of sleep is one of the simplest interventions for blood sugar management.

Monitoring your glucose: CGM and beyond

Continuous glucose monitors (CGMs) have moved beyond diabetes management into the biohacking and longevity space. These small sensors worn on the arm measure interstitial glucose every 1-5 minutes, revealing how individual foods, meals, exercise, and stress affect your blood sugar in real time. For non-diabetics, a 2-4 week CGM experiment can reveal personal trigger foods and optimal meal timing that no generic dietary advice can match ^[6].

However, CGM data in healthy people needs careful interpretation. A 2024 study in a large community cohort without diabetes found that standard CGM metrics don't correlate with HbA1c the same way they do in diabetics ^[7]. The technology is most useful for behavior modification — seeing a glucose spike in real time after a particular meal is more motivating than any nutrition lecture.

Supplements that support glucose regulation

Several supplements have evidence for improving insulin sensitivity. Magnesium supplementation for at least four months significantly improves HOMA-IR, a marker of insulin resistance ^[8]. Berberine activates AMPK and has shown glucose-lowering effects comparable to metformin in clinical trials. Chromium picolinate, alpha-lipoic acid, and inositol also have supporting evidence, though effect sizes tend to be modest. Supplements work best as additions to dietary and lifestyle changes, not replacements for them.