White and green teas, derived from the Camellia sinensis plant, have garnered attention for their potential health-promoting properties. A review by B. Abiri et al. (2023), published in Food Science & Nutrition, examines how the bioactive compounds in these teas may aid in weight management, cardiometabolic health, and the prevention of chronic diseases. Additionally, the review explores potential adverse effects, providing a balanced perspective on their role in human health.
Bioactive Compounds in White and Green Teas
- Phenolic Compounds:
- Rich in catechins like epigallocatechin gallate (EGCG), which provide potent antioxidant and anti-inflammatory effects.
- Phenolic compounds contribute significantly to their anti-obesity and cardioprotective properties.
- Caffeine:
- Acts as a mild stimulant and metabolism booster, aiding in weight management.
- Theanine:
- An amino acid that promotes relaxation and reduces stress, indirectly supporting cardiometabolic health.
- Flavonoids:
- Offer anti-inflammatory and vasodilatory benefits, enhancing heart health.
Anti-Obesity Properties of White and Green Teas
- Metabolism Enhancement:
- Catechins and caffeine synergistically boost metabolic rate, leading to increased calorie burning.
- Fat Oxidation:
- EGCG promotes fat breakdown, especially during physical activity, aiding in the reduction of visceral fat.
- Appetite Regulation:
- Tea polyphenols influence hormones like ghrelin and leptin, which regulate hunger and satiety, helping reduce calorie intake.
- Prevention of Fat Accumulation:
- Inhibits enzymes like pancreatic lipase, reducing fat absorption in the gastrointestinal tract.
Cardiometabolic Health Benefits
- Cardiovascular Protection:
- Improved Cholesterol Profiles: Reduces LDL cholesterol while increasing HDL levels.
- Blood Pressure Reduction: Catechins promote nitric oxide production, improving endothelial function and lowering blood pressure.
- Blood Sugar Regulation:
- Improves insulin sensitivity and reduces fasting blood glucose levels, making it beneficial for managing and preventing Type 2 diabetes.
- Anti-Inflammatory Effects:
- Polyphenols combat chronic inflammation, a key factor in the development of atherosclerosis and metabolic syndrome.
- Weight-Induced Risk Reduction:
- The weight-management effects of tea indirectly lower the risks associated with obesity-related cardiometabolic diseases.
Potential Adverse Effects
- Caffeine Sensitivity:
- Excessive consumption may lead to side effects such as jitteriness, insomnia, or increased heart rate in caffeine-sensitive individuals.
- Iron Absorption Inhibition:
- Phenolic compounds in tea can bind to non-heme iron, reducing its bioavailability and potentially leading to iron deficiency in at-risk populations.
- Liver Toxicity:
- High doses of tea extracts, especially green tea supplements, have been associated with rare cases of liver damage. Moderate consumption as a beverage is generally safe.
- Gastrointestinal Discomfort:
- Tannins in tea may cause stomach irritation or nausea if consumed on an empty stomach.
Recommendations for Safe and Effective Use
- Optimal Consumption:
- Drinking 2–4 cups of white or green tea daily provides health benefits while minimizing risks.
- Brew at appropriate temperatures (70–80°C for green tea, slightly cooler for white tea) to preserve bioactive compounds and avoid bitterness.
- Avoiding Excessive Supplementation:
- Rely on natural tea consumption rather than high-dose extracts to reduce the risk of adverse effects.
- Pairing with a Balanced Diet:
- Incorporating white or green tea into a diet rich in fruits, vegetables, and whole grains can amplify their health-promoting effects.
Future Research Directions
- Dose-Response Studies:
- More research is needed to identify the optimal quantities of white and green teas for specific health outcomes.
- Long-Term Clinical Trials:
- Large-scale human studies are required to confirm the long-term safety and efficacy of tea consumption.
- Personalized Nutrition:
- Investigating how genetic factors and microbiota interactions influence individual responses to tea compounds could improve dietary recommendations.
Conclusion
White and green teas are potent natural allies in the fight against obesity and cardiometabolic diseases. Their rich content of catechins, flavonoids, and other bioactive compounds provides a foundation for weight control, cardiovascular protection, and improved metabolic health. While generally safe, tea should be consumed in moderation, and individuals should be mindful of potential adverse effects. With growing evidence of their benefits, white and green teas continue to stand out as functional beverages in promoting long-term health and well-being.
Abiri, B., Amini, S., Hejazi, M., Hosseinpanah, F., Zarghi, A., Abbaspour, F., & Valizadeh, M. (2023). Tea’s anti‐obesity properties, cardiometabolic health‐promoting potentials, bioactive compounds, and adverse effects: A review focusing on white and green teas. Food Science & Nutrition, 11, 5818 – 5836. https://doi.org/10.1002/fsn3.3595.