February 4, 2011
The Missing Ingredient For More Efficient Muscles
(Ivanhoe Newswire) -- After taking a small dose of inorganic nitrate for three days, healthy people consume less oxygen while riding an exercise bike. A recent study traces that improved performance to increased efficiency of the mitochondria that power our cells. These results may offer one explanation for the well-known health benefits of fruits and vegetables, and leafy green vegetables in particular.
"We're talking about an amount of nitrate equivalent to what is found in two or three red beets or a plate of spinach," which Eddie Weitzberg of the Karolinska Institute in Sweden, was quoted as saying. "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."Up until a short time ago nitrate wasn't thought to have any nutritional value at all. It was even suggested that this component of vegetables may be toxic. Ultimately, Weitzberg and his colleague Jon Lundberg previously showed that dietary nitrate feeds into a pathway that produces nitric oxide with the aid of friendly bacteria found in our mouths. Nitric oxide has been known for two decades as a physiologically imperative molecule.
The study offers yet another benefit of nitrate and the nitric oxides that stem from them. It seems that the increased mitochondrial effectiveness is owed to lower levels of proteins that generally make the cellular powerhouses leaky. "Mitochondria normally aren't fully efficient," Weitzberg explained. "No machine is."
These novel results show that increased dietary nitrate can have a rather immediate effect, however, it's not yet clear what might happen in people who consume higher levels of inorganic nitrate over extended periods of time. It will be a natural next step to repeat the experiment in people with conditions linked to mitochondrial dysfunction, including diabetes and cardiovascular disease, to see if they too benefit from nitrates.
"Among the more consistent findings from nutritional research are the beneficial effects of a high intake of fruit and vegetables in protection against major disorders such as cardiovascular disease and diabetes," the researchers concluded. "However, the underlying mechanism(s) responsible for these effects is still unclear, and trials with single nutrients have generally failed. It is tempting to speculate that boosting of the nitrate-nitrite-NO pathway may be one mechanism by which vegetables exert their protective effects."
As an interesting aside, Weitzberg says that the benefits of dietary nitrates suggest that powerful mouthwashes may have a downside. "We need oral bacteria for the first step in nitrate reduction," he says. "You could block the effects of inorganic nitrate if you use a strong mouthwash or spit [instead of swallowing your saliva]. In our view, strong mouthwashes are not good if you want this system to work."
SOURCE: Cell Metabolism, 1 February 2011