New Research: Your Carb Choices Affect Immunity
High-GI Diets to Higher Infection Risk
We usually think of carbs as fuel — some “fast,” some “slow.”
But this 2025 study in Journal of Health, Population and Nutrition has revealed something surprising: the type of carbs you eat may affect your risk of viral infection.
Researchers tracked more than 3,000 adults and found that those eating diets highest in glycemic index (GI) and glycemic load (GL) — think sugary snacks, white bread, refined rice — had a dramatically higher risk of catching COVID-19.
Compared to the lowest group:
- High GI = 6x higher infection risk
- High GL = 54x higher infection risk
That’s not a typo.
Why This Matters for Your Health
It’s not just about COVID-19.
This study adds weight to the idea that blood sugar balance and metabolic health are key pillars of immunity.
Chronic spikes in blood sugar:
- Stress your immune system Increase inflammation
- Disrupt your microbiome (the gut bugs that protect you)
- Drain your energy and mental clarity
On the flip side, high protein, low-GI, fibre-rich foods help keep your blood sugar steady — feeding your microbiome and supporting your body’s natural defence systems.
(Add in some exercise too.)
Practical Takeaway
Collectively, we need to think beyond calories.
The quality of your carbs matters for energy, immunity, and even resilience to infection.
Your immune system will thank you.
