Red wine has recently been touted as a cure-all for heart ailments and its popularity has risen as a result. But there remains differing opinions as to the health benefits of red wine.

Red wine is made from fermented red and dark grapes where the skin is left on during the fermenting process. It is this skin that gives the wine its characteristic dark hue. White wine is produced in a similar fashion, although the grape skins are removed before fermentation.

Experts believe that substances in the grapes — especially in the skins — contribute to its heart-healthy nature. However, no one is really sure exactly what it is about wine that can make it advantageous to people looking to improve heart health.

Studies supporting red wine’s medical benefits suggest antioxidants in red wine called polyphenols help protect the lining of blood vessels in the heart. Polyphenols come in flavonoids and nonflavonoids. Flavonoids are brightly colored plant pigments that occur naturally in most fresh fruits and vegetables. Nonflavonoids are largely vitamins, minerals and other plant pigments. Resveratrol is a nonflavonoid that gets the bulk of the credit when speaking of red wine’s medical benefits. Resveratrol is purported to help prevent damage to blood vessels while reducing “bad” cholesterol and may prevent blood clots.

It is important to note that much of the research on resveratrol and red wine has been conducted on mice and other animals, not people. For humans to acquire the amount of resveratrol given to lab animals to equate to the same health benefits, a person would have to consume 100 to 1,000 bottles of red wine a day.

Alcohol, in general, may be heart-healthy because it thins the blood and improves circulation. This can be advantageous to individuals who already are facing blockages in arteries and need improved blood flow. But grapes alone may also relax blood vessels allowing blood to flow more easily.

Red wine also contains vitamin C and other healthy substances, which can improve overall health.

Although there are reasons to believe red wine can be a heart-healthy addition to one’s diet, doctors may be reticent to suggest it because alcohol use can present other problems, especially if it is abused. With this in mind, red or purple grape juice and whole grapes can be a viable alternative for those looking to get the benefits of resveratrol and other antioxidants without the down side of alcohol.

Grape juice provides much of the same benefits of red wine. Eating whole red or purple grapes does too, in addition to the benefit of fiber in one’s diet.

For those who want to go the red wine route, remember that alcohol should be consumed in moderation. That means one drink a day for women or up to two drinks a day for men.