One of the newest supplements to hit the shops claiming to help with weight loss is green coffee. It’s available as a concentrated extract, as a supplement or as an instant coffee blend and claims to be beneficial to heart health by reducing high blood pressure.
We look at the evidence for green coffee extract or GCE.
How is green coffee different from regular coffee?
Coffee beans are roasted to give them their distinctive dark colour and rich flavour. Green coffee beans are raw and unroasted. They contain a greater concentration of chlorogenic acid, a natural substance that can influence metabolic processes. Chlorogenic acid is partially destroyed during the roasting process but an average cup can still provide around 70-350mg. Studies on GCE in humans have used doses of 700-1100mg a day.
Weight for weight, green coffee contains the same amount of caffeine as regular roasted coffee, but most supplements provide around 20mg caffeine per capsule. With 2-4 capsules a day, this supplement provides a similar amount of caffeine as one cup of coffee. If you’re sensitive to caffeine these supplements aren’t for you. They are not recommended for use during pregnancy and breastfeeding.
In summary, the chlorogenic acid content of green coffee extract has been suggested to lower blood pressure, help the body control blood sugar levels, and act as a weight loss aid. However, the lack of high quality human studies means these claims remain unproven.
Although suggested as able to lower blood pressure, at least one study showed a rise in blood pressure in those taking green coffee supplements.
Based on current medical knowledge, there is no robust evidence to support taking green coffee or its extracts as a means to control blood pressure, blood sugar or weight.
Dietitian reviewed by Catherine Collins RD