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It’s basically a healthy-eating plan that features foods like kale, blueberries, green tea, apples, red wine and dark chocolate. What’s not to like, right?
The Sirtfood Diet (Hodder & Stoughton, 2016) was written by two nutritionists from England, and the diet is said to be responsible for singer Adele’s weight loss.
The foods they recommend are solid. The whole rationale for the diet, however, is a different matter.
The “sirt” in “sirtfoods” refers to a set of genes called the sirtuin genes, which have been found to be directly involved in longevity. Numerous experiments show that you can “turn on” those genes by restricting calories by 25 to 33%. Doing this essentially extends life in every species studied, from yeast cells to monkeys. But even though it extends life and improves multiple metabolic metrics, it’s a strategy that hasn’t been quick to catch on with humans for obvious reasons.
Then a Harvard University researcher named David Sinclair, PhD, discovered that trans-resveratrol, a plant chemical found in red wine and the skin of dark grapes, could accomplish the same thing as eating less calories without the annoying side effect of starving. The research was one of the reasons why trans-resveratrol has become such a popular supplement.
The problem is, we have no idea if sirtfoods also turn on the sirtuin genes. The docs who wrote the book think they do, but as far as I can tell they’re guessing.
We know cutting calories turns them on, we know resveratrol turns them on, and these guys guess that certain foods turn them on. Maybe they’re right, but I haven’t seen any research backing it up. That said, there’s no arguing that the foods they recommend are tied to wonderful health benefits.