What are tiny blood vessels that has walls thin enough for carbon dioxide and oxygen to be exchanged?

garcinia cambogia became popular worldwide after being featured on the dr. oz show in 2012.

it is a small, green fruit, shaped like a pumpkin.

the skin of the fruit contains hydroxycitric acid (hca). this is the active ingredient in garcinia cambogia extract, which is marketed as a diet pill.

how it works: animal studies show that it can inhibit a fat-producing enzyme in the body and increase levels of serotonin, potentially to reduce cravings (1, 2trusted source).

effectiveness: one study with 130 people compared garcinia against a dummy pill. there was no difference in weight or body fat percentage between groups.

a 2011 review that looked at 12 studies on garcinia cambogia found that, on average, it caused weight loss of about 2 pounds (0.88 kg) over several weeks.

side effects: there are no reports of serious side effects, but some reports of mild digestive problems.