Turns out that Popeye may have been onto something with all his spinach guzzling: Researchers in Sweden have found that nitrates in spinach reduce the amount of oxygen needed to power muscles by increasing the efficiency of mitochondria, the structures in cells responsible for energy production. Mitochondrial dysfunction is known to play a role in both diabetes and cardiovascular disease.
The scientists had a group of healthy volunteers ride an exercise bike after taking a small dose of inorganic nitrate, equivalent to 200–300 grams of spinach, for three days. The research team then analyzed samples taken from the participants’ thigh muscles, comparing them to samples taking when the participants had taken a placebo (inactive treatment) instead of the nitrate. The researchers found that the mitochondria of the muscle cells were significantly more efficient after the ingestion of the nitrate, requiring less oxygen to produce energy and producing more energy per oxygen molecule.
According to study co-lead Eddie Weitzberg, MD, PhD, of Karolinska Institutet in Sweden, “We’re talking about an amount of nitrate equivalent to what is found in two or three red beets or a plate of spinach… We know that diets rich in fruits and vegetables can help prevent cardiovascular disease and diabetes but the active nutrients haven’t been clear. This shows inorganic nitrate as a candidate to explain those benefits.”
The same research team has also recently shown that nitrates reduce blood pressure in healthy people and that, in laboratory animals, these substances counteract aspects of the metabolic syndrome, which can be a precursor to Type 2 diabetes. Other research in animal models has shown that nitrates may help protect against heart attack and stroke.
The researchers aren’t recommending that anyone begin taking nitrate supplements based on these findings, but suggest that further investigation into this possible mechanism for the protective effects of vegetables is warranted. A next step, the researchers say, is to repeat the study in people with mitochondrial dysfunctions such as those who have diabetes or cardiovascular disease.
To learn more about the research, read the article “Want More Efficient Muscles? Eat Your Spinach” or see the study’s abstract in the journal Cell Metabolism. And when you’re done with that, try one of these great spinach-based recipes: