5 Health Benefits of the Guava Fruit (Superfood Series)
The guava fruit is a tropical fruit that has a pleasant flavor reminiscent of fresh strawberries and pears. Aside from adding exotic flavor to smoothies, juice blends and fruit salads, guavas are also good for you. Many of the health benefits of the guava fruit have been attributed to the extremely high levels of vitamin C this tropical superfood contains. A 100-gram serving (3.5 oz) of fresh guava pulp contains about 228 milligrams of vitamin C – that's more than 4 times the amount of vitamin C in an equivalent serving of fresh oranges. In fact, guavas rank right there on top of the list of the world's best natural sources of vitamin C, along with a number of other superfoods such as camu camu, wild rosehips, kakadu plums, acerola, sea buckthorn berries, and baobab fruits.
To learn all about how the vitamin C and other nutrients in guavas can benefit your health, keep reading.
Guava Fruit Contains Ellagic Acid, an Anti-Cancer Compound
The guava fruit belongs to the myrtle family of plants, and like many other fruits in this family, guavas contain significant amounts of ellagic acid. If you regularly visit the HealWithFood.org website, you may already know that ellagic acid has immune-boosting qualities and that it has been shown to neutralize carcinogenic substances and promote apoptosis (self-destruction) of cancerous cells in test tube studies. Whether ellagic acid will have the same effects in humans, however, will still need to be evaluated in carefully-designed studies.
Benefits of Guava for the Skin
Foods that contain high levels of vitamin C (ascorbic acid) frequently pop up on lists of the best foods for wrinkle-free skin. The anti-wrinkle and anti-aging effects of vitamin C rich foods, such as the guava fruit, have been linked to the ability of vitamin C to stimulate the production collagen and elastin, structural proteins that help keep your skin firm and elastic. In addition, pink-fleshed guavas are also an excellent natural source of lycopene, a carotenoid pigment that has been shown to protect the skin from some of the damaging effects of the sun's ultraviolet rays.
Test tube studies also show that the guava fruit (especially red guava) has exceptionally strong antioxidant properties. As you may already know, antioxidants neutralize free radicals, highly reactive molecules that can cause damage to your body at the cellular level, increasing the risk of age-related diseases and signs of aging, including wrinkled and saggy skin. To give you an idea of how the guava fruit fares against other tropical superfoods, here's an overview of the antioxidant capacity of some exotic fruits, expressed as L-Ascorbic Acid Equivalent Antioxidant Capacity or AEAC (in mg per 100 grams of fruit):
- Sapodilla 3,396
- Strawberry: 472
- Plum: 312
- Star fruit: 278
- Guava: 270
- Grape (seedless): 264
- Snake fruit: 260
- Mangosteen: 150
- Avocado: 143
- Orange: 142
- Papaya: 141
- Mango: 139
- Kiwi: 136
- Cempedak: 126
- Apple: 79
- Rambutan: 72
- Banana: 48
- Tomato 38
- Honeydew melon: 20
- Watermelon: 12
Anti-Diabetic Properties of Guava Supported by Research
In Chinese folk medicine, guava fruits and guava leaf tea have been used for years as natural remedies for diabetes. To investigate whether there is any truth behind these health claims made about guava, Taiwanese researchers from the Department of Pharmacology of Tajen Pharmaceutical College gave guava juice to normal and alloxan-treated diabetic mice. Marked hypoglycemic action was observed in both groups of mice. The researchers also tested the effects of guava in humans and found that ingestion of guava had blood glucose lowering effects both in healthy volunteers and volunteers with type II diabetes (or adult-onset diabetes). Based on their findings, the researchers concluded that guava might indeed help improve and/or prevent adult-onset diabetes.
Guava – A Preventive Treatment for Heart Disease and Varicose Veins?
Foods rich in vitamin C may also help keep your heart and vascular system healthy. A study published in the peer-reviewed scientific journal Free Radical Biology and Medicine found that supplementation with vitamin C reduced the average CRP by 25% in study participants with high CRP levels. High CRP levels (plasma C-reactive protein levels) are considered one of the best predictors of cardiovascular disease, possibly even better than high cholesterol levels. In addition, the lycopene found in pink-fleshed guavas may further reduce the risk of cardiovascular disease in people who add this exotic superfood to their diets (one study found that men with the largest amount of lycopene in their body fat were half as likely to have a heart attack as men with the lowest levels of lycopene).
In addition to people with an increased risk of heart disease, people susceptible to developing varicose veins or venous insufficiency might reap extra health benefits by eating guava fruits and other foods that contain high amounts of vitamin C. As Vitamin C helps your body form collagen and elastin, connective tissues that are responsible for keeping your veins strong and toned, plus it may help improve circulation within your body. Therefore, it comes as no surprise that low levels of vitamin C have been associated with the development of varicose veins.
The benefits of vitamin C on the vascular system are thought to be stronger when vitamin C rich foods or supplements are consumed together with foods that are rich in vitamin E. Good food sources of vitamin E that also pair nicely with guava in smoothies and other dishes include sunflower seeds, almonds, avocados, and one of our favorite superfoods, the walnut.
Red Guava – A Natural Remedy for Exercise-Induced Asthma?
Vitamin C – abundant in guavas – is a natural anti-histamine, which is why vitamin C rich foods are often recommended to people with allergies or asthma. But red guavas also contain another potential anti-asthma nutrient: lycopene! A study published in the journal Allergy found that lycopene had a protective effect against exercise-induced asthma in some of the study participants. The researchers responsible for this study believe that the anti-asthma effects observed in the study participants might be attributable to the antioxidant properties of lycopene.
1. USDA's Nutrient Database for Standard Reference.
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