Green tea extract is heavily promoted for weight loss but does it actually work?
Tea is from the plant Camellia sinensis. Green tea differs from black tea because it is not fermented before it’s dried. This is why green tea contains more antioxidants than black tea does. The type of fermentation uses enzymes that “oxidize” the antioxidants, so they’re in much smaller amounts in black tea. These antioxidants are of the “catechins” family.
Green tea also contains some caffeine and it’s the effect of both of these compounds together that are thought to help with weight loss.
GREEN TEA VS GREEN TEA EXTRACTS
The difference between drinking green tea and taking it as a supplement is that the extracts are more concentrated. For example, the highest dose of the extract that seems to be safe is 9.9 g/day, which is equivalent to 24 cups of green tea. While this dose may be “safe”, it’s likely to come alongside some side effects.
GREEN TEA EXTRACTS FOR WEIGHT LOSS
- Green tea contains two main active ingredients, caffeine and antioxidants known as “catechins”.
- Green tea seems to improve the fat-burning effects of exercise. It may result in the loss of a few extra pounds in people who are overweight.
- A review of several studies calculated an average weight loss of 2.8 lbs after about 12 weeks.
- It seems that the catechins and caffeine work together to help with weight loss so caffeine free versions don’t seem to work as well.
- Green tea extracts seem to be more effective in people who don’t normally ingest a lot of caffeine.
SAFETY OF GREEN TEA EXTRACTS
You’ve probably heard about the concerns with green tea supplements. There have been reports of them being linked to cases of liver failure and even death but what is the real deal on the safety of green tea supplements?
- We still don’t really know the effects of long-term use of the extracts.
- Clinical studies show that up to 1.6 g of green tea extract at one time are safe for most people. At higher doses, some people may experience headache, dizziness, and nausea.
- Overall, hepatotoxicity (a.k.a. liver toxicity) from green tea extracts is rare, nonetheless, if you experience abdominal pain, dark urine or jaundice (yellowing of the skin), you should see your doctor and avoid supplements that contain green tea extracts.
- Some factors that may make someone more susceptible to liver injury are obesity, fasting, and/or glutathionine depletion.
HOW TO TAKE GREEN TEA EXTRACTS
Green tea extracts are approved in Canada for use as a source of antioxidants. They’re also approved to help with weight management, along with reducing calories and increasing physical activity.
- For weight management, Health Canada recommends consumption of green tea extract for a maximum of 12 weeks.
- If you take green tea extracts, you should take them as directed on the label, including taking them with food.
- Don’t take them if you:
- Have liver concerns,
- Have iron deficiency (it reduces absorption of iron),
- Are pregnant or breastfeeding.
- Discontinue if you experience any side effects.
- Also note that they may interact with certain medications, so see your doctor or pharmacist to be sure.
My final note is for you to really think about why you are taking a supplement for weight loss. Is it for a quick fix? Do you want big results fast? If your answers are yes, then your results, if any may be short term. No supplement will ever be able to fix a poor diet or lifestyle. It takes commitment, hard work and consistency for a healthier future but believe me, it’s well worth it!
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