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Showing posts with label Citrulline. Show all posts
Showing posts with label Citrulline. Show all posts

Wednesday, 12 August 2015

Watermelon: This fruit can help fight diseases and boost health, who knew?

Studies indicate that the watermelon can confer surprising health benefits.

AUGUST 10, 2015

This fruit can help fight diseases and boost health, who knew?
Watermelon is more than a tasty fruit, it can also help with a variety o; it can also help improve health. Photo: Freeimages.com

Healthwise



Watermelon may be the best dessert nature ever created, with its sweet juice cleverly bound inside that spongy red (sometimes yellow) matrix, and fully protected by psychedelic green rind.
Talk about a party orb.
But much like the thespian whose good looks overshadow brilliant acting skills, the watermelon’s sweet, colourful qualities have long undercut its attributes as a wholly nutritious fruit whose tasty powers hydrate, as well as heal.
And no matter how you slice it, this green cannonball of nutrition is attracting scientific attention as an elixir that reduces muscle pain after workouts and a whole lot more.
Studies have also shown beneficial effects on arterial plaque in cardiovascular disease, prostate and other cancers, erectile dysfunction, menopause, acid reflux, and potentially, Alzheimer’s disease, among others.
A recent study, for example, found that “watermelon extract supplementation reduces blood pressure and arterial stiffness” in older adults in cold weather, so it “can prevent the progression of hypertension and the hypertensive response to cold exposure”, said author Dr Arturo Figueroa-Galvez, associate professor at Florida State University’s department of nutrition, food and exercise sciences.
Watermelon is more than a tasty dessert; it can also help heal a variety of ailments and is good for hydration. – TNS
Watermelon may be able to boost health benefits including lowering inflammation that leads to prostate cancer, says research. Photo: TNS
Another of his studies found that the supplement also reduced ankle blood pressure in obese adults with hypertension.
Studies by others found that watermelon compounds reduced inflammation in prostate, gastrointestinal and other cancers, while a study published recently showed that lycopene, which provides the red pigmentation in watermelon and tomatoes, potentially reduced the inflammatory cascade of Alzheimer’s disease.
In April, yet another study found lycopene reduced reflux disease in animals, in part, by inhibiting acid pathways in the stomach.
“Watermelon is a pretty well-documented source of vitamin C, vitamin A and potassium,” said Dr Penelope Perkins-Veazie, a professor of horticulture in the Plants for Human Health Institute at North Carolina State University, United States. She said she’s been studying watermelon nutrients for 15 years.
Most noteworthy are watermelon’s two “secondary metabolites”, citrulline and lycopene, which have been the focus of recent research.
Citrulline, a non-essential amino acid, is abundant in watermelon, with yellow watermelons having four times that of red ones.
As it turns out, citrulline is involved in producing nitric oxide, a potent molecule that relaxes blood vessels and lowers blood pressure, “with benefits to the brain, heart and in a cycle of amino acids necessary to properly flush the kidneys”, said Dr Perkins-Veazie, who has a PhD in horticulture.
Lycopene is actually more abundant and more easily available in watermelon than tomatoes, where it’s bound up in cellular walls, even if tomatoes draw more research attention due to their importance in the American diet.
Dr Perkins-Veazie said lycopene shows clear benefits in reducing plaque build-up in arteries and preventing prostate cancer.
Botanically, watermelon is a fruit in the same cucurbit family as pumpkins, squash and cucumbers, which are often mistaken as vegetables.
The longstanding bias against watermelon stems from its 21 grams of carbohydrates, mostly sugars, in every two-cup serving, with only a single gram of fibre.
“People are concerned about the sugar, but compared to processed products, it tastes sweet but isn’t loaded with sugar,” Dr Perkins-Veazie said. “It’s counterintuitive, but there is an enzyme present to regulate the glucose.”
Despite the sugars (equally divided among sucrose, glucose and fructose), two cups of watermelon have only 80 calories with no fat, sodium or cholesterol.
“Using the same watermelon extract used in my previous human studies, watermelon supplementation did not increase body weight and improved blood lipids in rats,” Dr Figueroa-Galvez said.
Watermelon originated in southern Africa and became nature’s canteen. Rather than transport water long distances, travellers took watermelons, which are 92% water and don’t begin rotting for three weeks.
Stephanie Barlow, spokeswoman for the National Watermelon Promotion Board, said the fruit offers consumers health, value and versatility all year-round, all parts being edible, including the rind and seeds.
“We’re really focusing on health,” she said. “All pre-packaged foods have a smattering of health claims, so our health message has to be the strongest one.”
There are 1,200 varieties of watermelon grown in 96 countries, she said, noting that square ones are being grown in square containers in Japan so they fit into smaller refrigerators. There are even a few orange watermelons.
The 100 seeds in a watermelon are heavier than the flesh, she said, and act like marbles, damaging the flesh and causing them to rot more quickly. That helps explain why in the market today, she said, “It’s a landslide majority of seedless watermelons.” – Pittsburgh Post-Gazette/Tribune News Service

This post is on Healthwise

Monday, 11 November 2013

Watermelon Prevents Sore Muscles



November 4, 2013

4351.jpgDon’t you love how great it feels to take a hike, hit the gym, do some yard work or otherwise move your muscles? And don’t you hate how sore your poor muscles feel the next day? Ah, if only there were a way to get a good workout without suffering the after-aches.

There is, a new study suggests…and it’s not only simple and economical, it’s tasty, too. The secret weapon: Watermelon.

Though watermelon has a reputation for being mostly, well, water—plus natural sugar—it’s actually pretty nutritious. Watermelon is high in vitamins A and C…ounce for ounce, it contains more of the powerful antioxidant lycopene than the much touted tomato…and it is one of only a few foods that provides L-citrulline, an amino acid our kidneys use to make arginine, a powerful vasodilator that can improve blood flow.

Some studies suggest that L-citrulline boosts athletic performance by increasing the amount of oxygen brought to muscles during exercise, which is why L-citrulline supplements are marketed for athletes. The new study, however, suggests that there’s a better way than supplements to get your L-citrulline…and that soreness prevention rather than performance enhancement is the true benefit.


FROM LAB TO GYM


The first part of the study took place in the laboratory, with the purpose of determining L-citrulline’s bioavailability. Cells that mimicked the construction and function of the lining of human intestines were placed in petri dishes and exposed to one of three concoctions…
  • Natural watermelon juice, made by liquefying watermelon pulp in a juicer (this is basically what winds up in your digestive tract after you eat watermelon).
  • Watermelon juice that had been pasteurized by heating it to 175°F for 40 seconds (as commercially available bottled watermelon juice typically is to increase its shelf life).
  • An L-citrulline supplement mixed with water.

The researchers then measured the amount of L-citrulline that was absorbed by the intestine-like cells. Findings: Natural watermelon juice had a significantly higher absorption rate (18.87%) than the pasteurized juice (13.19%) or the supplement (11.85%)—meaning that the unadulterated watermelon juice provided the most bioavailable form of L-citrulline.

The next part of the study took place in a gym. Participants included physically active young men who, over the course of two weeks, performed the same exercise routine three times. Each time, one hour before starting their workouts, they drank 17 ounces of either natural, unpasteurized watermelon juice (containing 1.17 grams of L-citrulline)…unpasteurized watermelon juice enriched with extra L-citrulline (for a total of 6.0 grams of L-citrulline)…or a placebo drink (an infusion of fruits and other plants that did not contain L-citrulline). All of the drinks looked alike and had the same natural sugar content. Participants were not told what the drinks contained or what effects the researchers were looking for.

The men wore heart rate monitors while riding stationary bikes at a very heavy resistance setting. They periodically rated their perceived exertion levels during the workouts…and reported their degree of muscle soreness 24 hours and 48 hours after completing the exercise routines. Each participant did the workout on three separate occasions so that everyone’s reaction to each drink could be measured.

Results: Participants reported significantly less muscle soreness 24 hours after drinking watermelon juice than after drinking the placebo concoction. (After 48 hours, soreness levels were minimal no matter which drink was consumed.) Interestingly, post-exercise soreness ratings were the same with the natural watermelon juice as with the enriched watermelon juice—suggesting that the unadulterated juice provided enough L-citrulline to reduce muscle soreness, and that the extra dose of L-citrulline in the enriched juice did not provide any additional benefit.

Surprisingly, given L-citrulline’s reputation as a performance enhancer, there were no differences in cycling speed, heart rate or perceived exertion no matter which drink the participants consumed before their workouts. However, it’s possible that consuming watermelon might enhance performance not on the same day, but rather on subsequent days, by making your muscles less sore and therefore allowing you to work out harder. It’s also possible that, if you consistently consume watermelon, then this performance boost might be ongoing. Further research would be needed to explore that theory…and also to determine how helpful watermelon juice might be for other types of people, such as women, for novice exercises or for elite athletes. These researchers hope to do additional studies on watermelon juice in the near future.

In the meantime, though, if you’re anticipating a strenuous workout, why not pull out your juicer and make some watermelon juice or just eat some watermelon before you exert yourself to see if this keeps your muscles from aching afterward? To get the same 1.17 grams of L-citrulline used in the study, you would need to drink 17 ounces of watermelon juice…or eat about four cups of cut-up watermelon cubes.

Source: Encarna Aguayo, PhD, associate professor, department of food engineering, Universidad Politécnica de Cartagena, Spain. Her study was published in Journal of Agricultural and Food Chemistry

http://www.bottomlinepublications.com/content/article/diet-a-exercise/watermelon-prevents-sore-muscles