There's no single correct answer — but there are evidence-backed ranges.
Standard guideline
ADA suggests 45–60g carbs per meal, 15–20g per snack. That works out to 200–250g/day. It's a safe default, but many people get better results with less.
Low-carb (under 130g/day)
Strong evidence for HbA1c reduction, weight loss and reduced medication needs in type 2 diabetes.
Very-low-carb / keto (under 50g/day)
The Virta study showed 1.3-point HbA1c drops at one year. Hard to sustain long-term for many people.
Type 1 diabetes
Carb count matters less than carb consistency. The goal is precise insulin matching, which is easier with predictable amounts. Many type 1s thrive on 100–150g/day.
How to find your personal number
- Pick a starting point (start at 100g/day if you're new to low-carb)
- Track post-meal glucose with a CGM or fingerstick for 7 days
- If spikes routinely cross 180 mg/dL, reduce by 20g/day for the next week
- Continue adjusting until 90% of post-meal readings stay under 140 mg/dL
What to focus on instead of just totals
- Protein: 0.8–1.2g per kg body weight
- Fiber: 35g+/day
- Fat: fill the rest, prioritize olive oil, avocado, fatty fish, nuts
Quality matters more than total counts. 100g of carbs from beans and berries does not equal 100g from white bread.