什麼是玉米黃素?

Zeaxanthin Benefits

Zeaxanthin is a carotenoid molecule found in eye cells . Zeaxanthin has two important functions:

  • It forms a yellow pigment barrier that protects eye cells from the harmful effects of certain light sources, such as the sun.
  • It protects the eyes from dangerous free radicals and unstable molecules that steal electrons from healthy cells and cause damage (known as oxidation).
  • Once inside the body, zeaxanthin is attracted to the eyes. It enters the lens, the clear, curved structure toward the front of the eye, and the macula and fovea, the two parts of the retina or tissue that lines the back of the eye.

The macula is the most sensitive part of the retina and has the most photoreceptors. These special cells convert light into signals that the brain can interpret. Therefore, the macula is where the sharpest vision occurs. It is also responsible for your ability to perceive color.

Zeaxanthin and another carotenoid called lutein are the only dietary carotenoids that accumulate in the retina. Since zeaxanthin and lutein are present in large amounts in the macula, they are called macular pigments.

Meso-zeaxanthin is thought to be produced when your body breaks down other carotenoids, and you don't typically get it from your diet

Zeaxanthin uses

Research shows that zeaxanthin may help slow or prevent the progression of eye diseases such as cataracts and age-related macular degeneration (AMD), which are the leading causes of visual impairment and acquired blindness in the United States.

Supplement use should be individualized and reviewed by a healthcare professional. No supplement is intended to treat, cure, or prevent disease.

Age-related macular degeneration (AMD)

Some dietary sources of zeaxanthin have been studied as protective factors for AMD, which affects people 65 years and older.

A 2012 meta-analysis found that a diet rich in lutein and zeaxanthin reduced the risk of early-stage AMD developing into late-stage AMD by 26%. It also helps reduce the risk of early AMD by about 4%.
Likewise, a 2017 review found that lutein and zeaxanthin obtained through dietary sources and supplements may protect eyes against the progression of AMD.

A more severe form of macular degeneration, called wet macular degeneration, occurs when blood vessels in the macula grow and leak fluid. Dry AMD is one of the risk factors for wet AMD, but there are other risk factors, such as high blood pressure.

According to the American Academy of Ophthalmology, zeaxanthin may help prevent the progression of both types of AMD.

cataract

Consuming zeaxanthin and lutein may slow the formation of cataracts, which can cause blurred vision.
American Optometric Association. Lutein and Zeaxanthin – Nutrients beneficial to the eyes.

A 2017 review found that higher blood concentrations of lutein and zeaxanthin were associated with a reduced risk of nuclear cataracts, although evidence that lutein and zeaxanthin help reduce the risk of other types of cataracts is currently weak.

uveitis

Uveitis is inflammation or swelling of the uvea of ​​the eye. The uvea is located in the center of the eye and is responsible for supplying blood to the retina. Lutein and zeaxanthin may help slow this inflammatory process.

A 2015 in vitro study found that lutein and zeaxanthin have anti-inflammatory effects on human uveal cells. But it's worth noting that this study was conducted on cells in the laboratory, so it's impossible to know whether these effects would also occur in humans.

More high-quality studies in humans are needed before further conclusions can be drawn about the effectiveness of lutein and zeaxanthin in uveitis.

diabetic retinopathy

Diabetic retinopathy is a complication of diabetes in which uncontrolled blood sugar causes damage to blood vessels in the retina. Lutein and zeaxanthin reduce the oxidative processes that damage the eyes in this way.

A 2015 review looked at a series of animal studies that evaluated the effects of lutein and zeaxanthin in diabetic mice and rats. It was concluded that lutein and zeaxanthin have a protective effect against diabetes-related retinal changes.

However, because these studies were conducted in rodents, there is no evidence that these effects occur in humans.

What are the side effects of zeaxanthin?

Researchers found no side effects or negative interactions with zeaxanthin.
American Optometric Association. Lutein and Zeaxanthin – Nutrients beneficial to the eyes.

However, people with fair skin may experience yellowing of the skin if the maximum recommended daily dose for adults (10 mg) is exceeded.

Precaution

There does not appear to be a risk in consuming too much lutein and zeaxanthin on a daily basis through supplements or diet.

While zeaxanthin supplements have not been found to cause any adverse side effects, their long-term use has not been studied. In fact, researchers are not sure whether taking synthetic forms of zeaxanthin lasts longer than five years.
Bright Focus Foundation. Lutein and zeaxanthin prevent macular degeneration.

Therefore, zeaxanthin supplements are only recommended for those who are very concerned about worsening vision loss.

If you're looking for a decades-long plan to support eye health, focus on eating fruits and vegetables every day.

Dosage: How much zea yellow should I take?

Always check with your healthcare provider before taking supplements to make sure the supplement and dosage are appropriate for your individual needs.

Generally speaking, health experts recommend that adults eat five servings of fruits and vegetables each day, which should provide about 5 milligrams of carotenoids (including zeaxanthin and lutein).

Currently, there is no recommended daily intake of zeaxanthin. However, taking at least 2 mg appears to have health benefits.

Research shows that when people consume 5-6 mg of zeaxanthin per day, the risk of AMD is lowest and cataract growth is slowed.

Through diet alone, you can get 5-10 mg of zeaxanthin and lutein from a variety of whole foods.

Zeaxanthin and lutein can be taken at any time of day, but mealtimes are usually best. As a fat-soluble antioxidant, zeaxanthin requires some fat to be absorbed properly.

Try spraying your vegetables with olive oil to help ensure you're getting the most out of the zeaxanthin they contain. Or, if taking a supplement, take it with food.

Sources and Precautions of Zeaxanthin

If you haven't been diagnosed with macular degeneration, health experts recommend increasing your zeaxanthin intake by eating foods rich in this micronutrient. This recommendation includes people who may be at risk for AMD, such as family members of diagnosed patients or smokers, who are four times more likely to develop AMD than people who have never smoked.

Macular Association. Smoking and vision loss. According to the American Optometric Association, broadening your diet to include foods rich in carotenoids is a promising way to protect your eyes from disease.

Food sources of zeaxanthin

Zeaxanthin occurs naturally in a variety of fruits and vegetables. Dark leafy green vegetables are especially rich in zeaxanthin. Because they contain the highest content of carotenoids. In fact, zeaxanthin is responsible for the rich color of these foods, as it modulates light energy and keeps chlorophyll at the proper levels during photosynthesis. The chlorophyll in dark green vegetables actually masks the pigments lutein and zeaxanthin, giving the vegetables their recognizable green color.

Scientific information often lists foods containing zeaxanthin and lutein as one category, rather than listing them separately. This may be because lutein can be converted to the carotenoid meso-zeaxanthin in the eye, but also because zeaxanthin is low in the human diet.

But you shouldn't just eat a few vegetables. In addition to green vegetables, eggs and brightly colored fruits and vegetables are good sources of zeaxanthin and lutein.

Foods that provide the carotenoids needed for eye health include:

  • Egg
  • kale
  • spinach
  • Swiss Chard
  • lettuce
  • mustard
  • Radish leaf vegetables
  • kale
  • Watercress
  • Haricot vert
  • squash
  • pumpkin

Zeaxanthin Supplements

Zeaxanthin-containing supplements and eye health supplements are becoming more and more popular.

Studies show that taking zeaxanthin increases the density of macular pigment in the eyes.

One study had people take zeaxanthin supplements for 6 to 24 months. Studies have found that 36-95% of humans have increased macular pigment density. Interestingly, this reaction varies from person to person.

Higher macular pigment density is associated with a lower risk of AMD.

Note that the FDA does not regulate dietary supplements to the same extent as pharmaceuticals, except that it prohibits unsubstantiated health claims. The FDA or the European Food Safety Authority (EFSA) have not approved any health claims for zeaxanthin supplements.

generalize

Zeaxanthin is a carotenoid, a pigment that gives orange and yellow fruits and vegetables their bright colors. Along with the carotenoid lutein, zeaxanthin can help slow or even prevent the progression of cataracts and age-related macular degeneration. If you have been diagnosed with vision loss and are unable to get between 6 mg and 10 mg of both carotenoids in your diet, consider taking supplements to fill the gap.

Review

All comments are moderated before being published

HealthyPIG Magazine

View all
光學治療濕疹 - 全面總結

光學治療濕疹 - 全面總結

簡介 光療使用光波來治療某些皮膚問題。皮膚會暴露於紫外線 (UV) 光下一段設定的時間。光療利用人造的紫外線光源,紫外線也來自陽光。當與一種叫做甲氧補骨脂素的藥物一起使用時,這個程序稱為 PUVA 光療。 紫外線光能夠抑制皮膚中的免疫系統細胞,對於因免疫系統過度反應引起的皮膚問題有幫助。可以使...
什麼是「操縱者」?

什麼是「操縱者」?

操縱者,也可以說成「擅用手段的人」,「心機重的人」。操縱者利用欺騙、影響或者其他形式的心理操控來控制或影響他人,以達到自己的目標。他們的行為通常包含使用隱蔽、間接或偷偷摸摸的手法來獲得他們想要的東西,往往是以犧牲他人為代價。以下是一些常見的特徵和手段: 欺騙: 他們可能會說謊或扭曲事實來誤...
什麼是肌肉抽搐?你需要去看醫生嗎?

什麼是肌肉抽搐?你需要去看醫生嗎?

肌肉抽搐,也稱為肌束顫動,是指身體各部分出現不自主的肌肉收縮。以下是肌肉抽搐的原因、症狀及管理方法的詳細介紹: 肌肉抽搐的原因 壓力和焦慮 高水平的壓力和焦慮會導致肌肉緊張和抽搐。身體對壓力的反應會觸發神經系統,導致肌肉不自主地收縮。 疲勞 過度使用或劇烈運動後的肌肉疲勞會導致肌...
蘋果與牙齒健康:保護牙齒的小技巧

Apples and Dental Health: Tips to Protect Your Teeth

Apples are widely loved for their rich nutritional content and refreshing taste. However, apples' acidic and sugary content may also have an impact...
蘋果籽的毒性:它們真的有毒嗎?

Apple Seed Toxicity: Are They Really Poisonous?

Apple seeds contain cyanogenic glycosides, compounds that break down in the body to produce cyanide, which has raised concerns about the toxicity o...
有機蘋果與傳統蘋果:哪個更健康?

Organic apples vs. conventional apples: Which one is healthier?

Apple is one of the common fruits in our daily life, but when choosing, many people are confused whether to choose organic apples or traditional ap...
艾草:益處,營養,副作用,評論和推薦產品

Wormwood: Benefits, Nutrition, Side Effects, Reviews and Recommended Products

Highlights What is Artemisia? Background and history health benefits Instructions drug interactions Side effects and disad...
紅麴米:益處,營養,副作用,評論和推薦產品

Red Yeast Rice: Benefits, Nutrition, Side Effects, Reviews and Recommended Products

Highlights What is Red Yeast Rice? Background and history health benefits Instructions drug interactions Side effects and ...
什麼是草藥膏?

What is herbal ointment?

Highlights What is Herbal Salve? Background and history health benefits Instructions drug interactions Side effects and di...