Where your DNA places you among other people, and the studies behind it.
Not tailored to your result, and not medical advice
Reduce Refined Carbohydrate Intake: Refined carbohydrates and added sugars produce rapid glucose spikes that contribute to hemoglobin glycation. Replacing them with whole grains, legumes, and other high-fiber foods is associated with lower postprandial glucose and modest reductions in HbA1c in randomized trials. PLOS Medicine
Exercise Consistently: In people with type 2 diabetes, structured exercise training is associated with an average HbA1c reduction of about 0.67%, with similar benefit from aerobic, resistance, and combined training. More than 150 minutes per week is associated with larger reductions, so consistency matters. JAMA
Manage Body Weight: Excess body fat, particularly visceral fat, is a major driver of insulin resistance and higher glucose. In the Diabetes Prevention Program, an intensive lifestyle program targeting about 7% weight loss and 150 minutes of weekly activity reduced progression to type 2 diabetes by 58% in high-risk adults. New England Journal of Medicine
Know Where Your HbA1c Sits: HbA1c reflects average blood glucose over roughly three months, so it catches a drifting trend that a single reading would miss. It is a routine blood test, and knowing your own number gives lifestyle changes something concrete to move. CDC
Optimize Sleep and Stress: Experimental sleep restriction reduces whole-body insulin sensitivity by roughly 20-25%, and chronic stress raises cortisol, both of which can push average glucose upward. Prioritizing adequate sleep and managing stress may help support glycemic control alongside diet and exercise. PMC
How much of this is genetic?
Genetics explains 50% of why people differ in this trait. The rest is environment, daily habits and chance.
Heritability estimate: Simonis-Bik et al. 2008, Twin Res Hum Genet
Background and further reading
HbA1c (glycated hemoglobin) measures the percentage of hemoglobin molecules that have glucose attached to them. Because red blood cells circulate for roughly 120 days, HbA1c reflects average blood glucose over the preceding 2-3 months. It is more stable than a single fasting glucose reading and is used both to diagnose diabetes and to monitor long-term glucose control. Under American Diabetes Association criteria, an HbA1c below 5.7% is normal, 5.7-6.4% indicates prediabetes, and 6.5% or higher indicates diabetes.[1]
Genetic Basis: Twin studies place the heritability of HbA1c in non-diabetic people at roughly 40-60%.[2] A large multi-ancestry genome-wide meta-analysis of up to ~159,000 people identified about 60 common variants and classified them into two biologically distinct groups: glycemic variants, which affect insulin secretion and glucose regulation and track with type 2 diabetes risk, and erythrocytic (non-glycemic) variants, which act through red blood cell and hemoglobin biology rather than glucose.[3] Because erythrocytic variants - for example in HBB, ANK1, or G6PD - shift HbA1c without changing actual blood sugar, they can make HbA1c a misleading diabetes test in some carriers. The G6PD A− variant (rs1050828), common in people of African ancestry, lowers HbA1c and can mask hyperglycemia.[3][4]
Environmental Factors: Because HbA1c reflects average glucose, most factors that influence blood sugar influence it: diet quality, physical activity, body weight, stress, and sleep. In trials, higher dietary fiber and whole-grain intake is associated with modest reductions in HbA1c,[5] and short sleep and chronic stress are linked to reduced insulin sensitivity and higher glucose.[6] Separately, conditions that change red blood cell turnover - such as iron-deficiency anemia, recent blood loss, hemolysis, or advanced kidney disease - can raise or lower HbA1c independently of glucose, so results should be interpreted in context. Its weeks-to-months averaging makes HbA1c a better marker of sustained habits than a single glucose measurement.
The published research behind your score, and the variants it draws on.
28 published scores from 9 studies
The HbA1c score combines 28 polygenic scores drawn from 9 published studies.
Chen J (2021). The trans-ancestral genomic architecture of glycemic traits. Nat Genet: 1.0M
These traits are influenced by some of the same genes and variants as this one
Body Mass Index: A measure of body weight relative to height, used as a proxy for overall adiposity.
Content updated August 2026.
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