Eat foods rich in nitrates, which your body eventually turns into nitric acid
Include beetroot, celery, lettuce, rocket, spinach, celeriac and parsley
Nitric oxide tells your blood vessels to expand and lowers blood pressure
Eat foods rich in nitrates, which your body eventually turns into nitric acid
Asked what nitric oxide gas is, many people might suggest it’s ‘hippy crack’, the legal high that’s landed so many Premier League footballers in trouble.
In fact that’s nitrous oxide. But thanks to some recent and dramatic discoveries, nitric oxide could soon be far better known — for its many health benefits, rather than any dangers.
It’s already known that nitric oxide, a gas produced naturally by the body and carried in the blood, tells your blood vessels to expand, so lowering blood pressure. That’s why beetroot in particular is so good for blood pressure — the body converts the nitrites in this veg into nitric oxide.
Researchers have since found nitric oxide does a lot more, including helping you to sleep and fight off infections.
And now it turns out we have large, totally unexpected stores of it under our skin, and that our blood cells don’t work properly without it.
This could lead to a total rethink on safe sun advice, the way heart patients are treated, and even how blood transfusions are performed.
It could also mean that boosting our nitric oxide levels — by eating more veg such as celery, or exercising more — could help prevent diseases including diabetes and cancer.
Until a few years ago, no one knew that blood cells even carried nitric oxide. Now we realise that it plays a vital role in ensuring cells get the oxygen they need, as research at the Case Western Reserve University School of Medicine in Cleveland in the U.S. has found.
‘Cardiologists have always assumed that if your blood was carrying a normal amount of oxygen, the gas would automatically get into cells,’ Jonathan Stamler, the lead researcher and a professor of medicine, told Good Health. ‘Now it looks like that was wrong.
‘What we’ve discovered is that the oxygen carried in blood cells can’t be delivered into the body’s cells unless it comes with nitric oxide. ‘When you put red blood cells and blood vessels together in the lab, the blood vessels close up. We eventually worked out that the cells were missing nitric oxide. It was lost when you took the blood cells out of the body.’
The thinking is that a lack of the gas could cause problems generally linked to poor blood flow, such as heart attack, heart failure, stroke, damage to the kidneys and poor circulation in the legs.
But his discovery also alerted Professor Stamler to a problem with transfusions. ‘Stored blood loses its nitric oxide, which means that transfusions generally fail to deliver the oxygen that cells may desperately need,’ he says.
‘Transfusions do help when there’s been massive blood loss, but in most cases there is only modest blood loss. Cardiologists have long been puzzled by how patients could have enough oxygen in the blood, but lack it in the cells. Now we have the answer.’
Foods include beetroot, celery, lettuce, rocket, spinach, celeriac and parsley
IT’S VITAL FOR HEALTHY CELLS
So how can a gas hitch a ride on blood cells? By staying as a gas for only a few seconds at a time.
Nitric oxide binds very easily with other compounds such as proteins, enzymes and genes. When it gets loaded on to red blood cells it ‘sticks’ to the protein haemoglobin, which carries the oxygen.
‘This ‘stickiness’ of nitric oxide means it can create thousands of similar combinations all over the body,’ says Professor Stamler. ‘One such combination occurs in the brain, where nitric oxide links with one of the proteins that is essential for memory function. So losses in nitric oxide may be a factor in Alzheimer’s.’
Professor Stamler’s discoveries are based on animal studies. But in a separate, unique experiment on humans, Martin Feelisch — a professor of experimental medicine and integrative biology at the University of Southampton — has looked at what happens when cells run short of oxygen (which seems to be what happens when nitric oxide isn’t loaded on to blood cells).
He used climbers scaling Mount Everest, explaining: ‘The air gets thinner the higher you go, so you get less of it as you breathe in.’
So mountaineers provide a picture of what happens to the rest of us if we don’t have enough nitric oxide.
Professor Feelisch’s volunteers took regular blood samples as they ascended and he found that they had twice the normal amount of insulin, a rise in damaging oxidants and also a rise in inflammation.
Stored blood loses its nitric oxide, which means that transfusions generally fail to deliver the oxygen that cells may desperately need
There was also a change in the way their cells made energy. ‘The tiny energy-producing units in every cell called mitochondria that need oxygen were becoming less efficient, so the cells were switched to using more glucose or energy,’ he says. ‘This shows that a lack of nitric oxide could be one of the things that goes wrong in diabetes, opening up the possibility of new treatments.’
This change in energy production is also found in cancer, says Professor Feelisch. ‘It’s not clear yet what the implication is, but it could well be that low oxygen triggers or promote cancer.’
But this is not the only exciting discovery…
HERE’S WHY THE SUN CUTS BLOOD PRESSURE
We’ve known for years that vitamin D is vital for strong bones and teeth. More recently, research has suggested it is also linked to a lower risk of heart disease.
But it may be that it’s not the vitamin that’s good for the heart. According to research from Edinburgh University, it’s nitric oxide.
A team headed by Professor Richard Weller, a senior lecturer in dermatology, made the completely unexpected discovery that our skin contains large stores of nitric oxide which are released into the blood when exposed to the UVA rays in sunlight. To get vitamin D you need UVB, the burning rays linked to cancer.
Vitamin D is linked to a lower risk of heart disease
Professor Weller believes vitamin D’s reputation for heart protection has been piggy-backing on the benefits of UVA. ‘The result is that a fairly short sun exposure can lower your blood pressure,’ he says.
Professor Weller’s research, which has so far been carried out on animals, has put him on a collision course with conventional wisdom — and colleagues.
‘I’m a dermatologist,’ he says. ‘I spend my days seeing people with skin cancer and telling them to be careful of the sun. But now I believe that protecting against heart disease and stroke trumps the risk of skin cancer. Leaving aside malignant melanoma, skin cancer doesn’t actually increase your overall risk of dying. Although it is more common than all the other cancers put together, it can be effectively treated by cutting it out.
‘Heart disease and stroke, on the other hand, can kill you. Deaths from heart disease are 100 times higher than deaths from skin cancer.’
He, like Professor Stamler, stresses that further studies on humans are needed to clarify what is the optimum sun exposure to recharge and release the skin’s stored nitric oxide, and whether artificial UV could be safe and beneficial.
‘Don’t shun the sun,’ he adds. ‘Enjoy it — but without getting burnt.’
WAYS TO BOOST LEVELS OF THIS WONDER GAS
Nitric oxide is thought to be particularly important for older people, whose levels drop with age, according to research from the University of Texas Health Science Centre published in 2011. And there are already a number of drugs in the pipeline aimed at boosting nitric oxide supplies.
30%
The proportion of people in England who have high blood pressure
But the best way to keep your supplies topped up is through diet, especially foods rich in nitrates, which your body turns into nitric acid with the help of bacteria found in your saliva.
These include beetroot (particularly rich in nitrates), along with celery, lettuce, rocket, spinach, celeriac and parsley.
Our bodies can also make nitric oxide from an amino acid called L-arginine, found in nuts, meat, fruits, dairy products, chocolate and raisins.
We should also avoid things that can cut down our supply of nitric oxide.
Antibacterial mouthwashes don’t do the bacteria in your saliva any favours, nor does the long-term use of heartburn drugs known as PPIs (proton pump inhibitors). These cut production of stomach acid by 90 per cent — but stomach acid is vital for turning nitrates from food into nitric oxide.
We also make nitric oxide when we exercise, because it stimulates cells in the lining of our blood vessels to make more from L-arginine.
But the real message of all the new discoveries, according to Professor Feelisch, is that we ignore at our peril the important role of the world around us in keeping us healthy.
‘Nitric oxide has been vital for the survival of animals for hundreds of millions of years,’ he says. ‘We have evolved to get it from our food and to make more of it when we exercise or go out in the sun.
‘But in the past 150 years we have adopted a way of living that cuts the amount of nitric oxide we can get from those sources. Now we are paying a price in the rise of obesity, diabetes and other chronic diseases.’
Source: Daily Mail
