2 weeks Ago By [email protected] (Neil Shaw)
Eating four helpings of cheese a day can protect your blood vessels against damage from salt, scientists say. Too much salt in your diet causes high blood pressure and can damage blood vessels, causing heart problems. Researchers believe it is the antioxidants in cheese that have the effect and all dairy products could also be beneficial for heart health.
The team from the Pennsylvania State University found that when adults consumed a high sodium diet, they also experienced blood vessel dysfunction. But in a randomised, crossover design study, when the same adults consumed four servings of cheese a day alongside the same high sodium diet, they did not experience this effect. Study author Dr Billie Alba said: "While there's a big push to reduce dietary sodium, for a lot of people it's difficult.
Possibly being able to incorporate more dairy products, like cheese, could be an alternative strategy to reduce cardiovascular risk and improve vessel health without necessarily reducing total sodium." The researchers recruited 11 adults without salt-sensitive blood pressure for the study. They each followed four separate diets for eight days at a time: a low-sodium, no-dairy diet; a low-sodium, high-cheese diet; a high-sodium, no-dairy diet; and a high-sodium, high-cheese diet.
The low sodium diets had participants consume 1,500 mg of salt a day, while the high sodium diets included 5,500 mg of salt per day. The cheese diets included 170 grams, or about four servings, of several different types of cheese a day. At the end of each week-long diet, they returned to the lab for testing.
The researchers inserted tiny fibres under the subjects' skin and applied a small amount of the drug acetylcholine, a compound that signals blood vessels to relax. By examining how each participants' blood vessels reacted to the drug, the researchers were able to measure blood vessel function. They also underwent blood pressure monitoring and provided a urine sample to ensure they had been consuming the correct amount of salt throughout the week.
The researchers found that after a week on the high sodium, no cheese diet, their participants' blood vessels did not respond as well to the acetylcholine and had a more difficult time relaxing. But this was not seen after the high sodium, high cheese diet. Lacy Alexander, professor of kinesiology at Penn State and another researcher on the study published in the Journal of Nutrition said: "While the participants were on the high-sodium diet without any cheese, we saw their blood vessel function dip to what you would typically see in someone with pretty advanced cardiovascular risk factors.
"But when they consumed the same amount of salt, and ate cheese as a source of that salt, those effects were completely avoided. Studies have shown that people who consume the recommended number of dairy servings each day typically have lower blood pressure and better cardiovascular health in general. "We wanted to look at those connections more closely as well as explore some of the precise mechanisms by which cheese, a dairy product, may affect heart health.
" Dr Alba said that while the researchers cannot be sure that the effects are caused by any one specific nutrient in cheese, the data suggests that antioxidants in cheese may be a contributing factor. She said: "Consuming high amounts of sodium causes an increase in molecules that are harmful to blood vessel health and overall heart health. "There is scientific evidence that dairy-based nutrients, specifically peptides generated during the digestion of dairy proteins, have beneficial antioxidant properties, meaning that they have the ability to scavenge these oxidant molecules and thereby protect against their damaging physiological effects.
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