November is Diabetes Prevention Month in Japan, with awareness campaigns taking place across the country. As people start paying more attention to body-fat management, various diet methods attract interest. Among them, grapefruit often gets featured on TV because it’s easy to try and is said to work simply by smelling its aroma.
Grapefruit contains limonene, which is believed to activate the sympathetic nervous system. This may help boost blood flow and metabolism, easing swelling and cold sensitivity. It’s also thought to stimulate fat-breaking enzymes, making fat easier for the body to burn. Some suggest that smelling its scent before meals can help reduce appetite.
A U.S. research team studied 91 adults with obesity and divided them into four groups:
- half a fresh grapefruit + placebo capsule
- grapefruit juice + placebo capsule
- grapefruit capsules + apple juice
- placebo capsule + apple juice
Participants took their assigned items three times a day before meals.
After 12 weeks, the results showed:
- Fresh grapefruit: –1.6 kg
- Grapefruit juice: –1.5 kg
- Grapefruit capsules: –1.1 kg
- Placebo: –0.3 kg
All grapefruit groups lost significantly more weight than the placebo group. They also showed a notable decrease in insulin levels during glucose tolerance testing. The researchers concluded that while the exact mechanism isn’t clear, adding grapefruit to a weight-loss diet “seems reasonable.”
However, there’s an important caution: grapefruit and grapefruit products can increase the risk of side effects if you’re taking immunosuppressants or certain blood pressure medications. It’s not suitable for everyone, so it’s best not to follow TV or online trends without thinking. If you’re on medication, check with your doctor or pharmacist first.
For diabetes prevention, the key is reducing body fat in a healthy way while maintaining muscle mass. It’s great to explore different methods to support long-term lifestyle changes, but remember that the basics of weight management never change: eat a balanced diet in the right amounts and stay active.