Doctors Reveal That Eating Onions Causes… Good Things!
3. May Help Regulate Blood Sugar
For people managing prediabetes or type 2 diabetes, onions could be a supportive food.
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A compound called S-methylcysteine sulfoxide has shown promise:
In one study, participants who ate raw red onion saw lower fasting blood glucose after meals
Effects were seen within 2–4 hours
Not a replacement for medication — but a helpful addition to balanced meals.
4. Boosts Immune Function
While no food “boosts” immunity overnight, onions support your body’s defenses through:
Vitamin C → white blood cell production
Antioxidants → protect cells from damage
Prebiotic fiber → feed beneficial gut bacteria (your immune system lives largely in your gut)
Regular consumption helps maintain readiness — not overstimulation.
5. Promotes Digestive Wellness
Onions contain inulin and fructooligosaccharides (FOS) — types of prebiotic fiber.
These do not digest in the small intestine.
Instead, they travel to the colon, where good bacteria ferment them — producing short-chain fatty acids like butyrate, which:
Nourish colon cells
Reduce gut inflammation
Improve bowel regularity
Note: For people with IBS, onions (especially raw) can trigger bloating due to FODMAPs — cook them lightly to reduce impact.
6. Contains Compounds Being Studied for Cancer Prevention
Epidemiological studies show a correlation between higher allium vegetable intake (onions, garlic, leeks) and lower risk of certain cancers — particularly stomach and colorectal cancers.
