What Is Niacin and Why Is It Important for Your Eyesight?

Niacin is one of the key ingredients in vitamin supplements many people take every day. It plays an essential role in maintaining your overall health and has a beneficial effect on your eyesight, protecting against glaucoma.

In this post, we’ll explain why taking niacin supplements regularly prevents the loss of eye function, as well as what other health benefits you can derive from it.

What Is Niacin?

Niacin is one of the vitamins in the B group. Also known as B3, niacin comes in two forms: nicotinic acid and nicotinamide (or niacinamide).

You can find both in dietary supplements, but you can also get all the B3 that you need from your food.

B3 is a water-soluble vitamin, which means that your body doesn’t store it, so any surplus will be eliminated through urine.

What Does Niacin Do?

Niacin’s most important role is in metabolism, helping the body transform food into energy. The absorbed niacin is converted into the coenzymes NAD and NADP, which play a key role in metabolic reactions at the cellular level.

Adequate niacin intake protects the nervous system, maintains brain function, and helps the digestive system.  It also acts as an antioxidant, preventing the damage caused by free radicals.

Good to know: The recommended daily intake of niacin is 14 mg for adult women and 16 mg for men. This refers to healthy adults, not people with high blood pressure or glaucoma, who need to take higher doses.

Why Is Niacin Essential for Eye Health?

Two eyes side by side

Recent studies show that vitamin B3 can prevent glaucoma, a progressive eye condition that can lead to blindness. Glaucoma is not just one disease but several conditions that damage the optic nerve.

It progresses slowly, without noticeable symptoms—many people discover they have glaucoma when it’s already very advanced. The best thing you can do is try to prevent optic nerve damage in the first place.

A Korean study published in 2018 found that adults with low vitamin B3 intake are at a higher risk for developing intraocular blood pressure, which is the main cause of open-angle glaucoma.

At the same time, a study on mice came to the conclusion that niacin supplements prevent optic nerve damage and glaucoma. According to the researchers, who administered B3 supplements to glaucoma-prone mice, niacin was very effective in the prevention of glaucoma.

A pioneering clinical trial that took place in Australia found that patients who received vitamin B3 supplements showed significant improvement in eye function. The patients were put on 1.5 grams of niacin per day for six weeks. During the second phase of the trial, the dosage was increased to 3 grams per day.

Does this mean that you should start taking high doses of niacin every day? Niacin supplements are not without risks. Very high doses of niacin can cause blurry vision, inflammation of the cornea, and macular damage. You should always talk to your doctor to determine the optimal levels of niacin for you.

What Are the Main Food Sources for Niacin?

peanuts on green background

Taking B3 supplements may pose certain risks, but increasing your niacin intake through diet is thought to be perfectly safe. The good news is that niacin can be found in great amounts in a variety of foods, including:

  • Beef liver
  • Chicken breast
  • Turkey breast
  • Roasted peanuts
  • Brown rice
  • Fish (salmon, tuna)
  • Mushrooms

For instance, a 3-ounce serving of grilled chicken breast provides 64% of the niacin recommended daily intake. That is well below the dosage used to treat glaucoma, but it’s a step in the right direction. You should also look for foods fortified with niacin, such as breakfast cereals.

What Are the Main Niacin Health Benefits?

Many people first hear of niacin when they are put on it as part of their treatment for high blood pressure. Let’s have a look at other benefits of taking niacin.

Reducing Blood Pressure

Niacin is often prescribed to treat people with high blood pressure because this vitamin plays an important role in the release of prostaglandins, lipid compounds that help widen blood vessels. When blood vessels are wider, blood flows easier, so your blood pressure drops. This also reduces the strain on your heart, which doesn’t need to pump so hard to keep the blood circulating. According to one study, a daily dose of 14.3 to 16.7 mg of niacin significantly lowers the risk of developing high blood pressure.

Improving Cholesterol Levels

If you’re worried about your cholesterol levels, a good diet and niacin supplements can help you keep blood fat levels under control. Taking vitamin B3 daily can reduce triglyceride levels and LDL (bad cholesterol) levels while increasing HDL (good cholesterol) levels. One recent study showed that you should take 1.5 grams of niacin daily to see a serious improvement in blood fat levels.

Keeping Type 1 Diabetes Under Control

Type 1 diabetes is a chronic disease in which the pancreas doesn’t produce enough insulin, which is needed to help blood sugars enter cells and be converted into energy. It’s often diagnosed during childhood, which is why it’s also known as juvenile diabetes.

New research shows that children at risk of developing type 1 diabetes could benefit from vitamin B3 supplements. The bad news is that niacin does not appear to be useful for people suffering from type 2 diabetes.

Improving Brain Function

Your brain consumes a lot of energy, which is why you need niacin and the coenzymes NAD and NADP it converts to. Niacin deficiency can lead to brain fog as well as psychiatric conditions, including schizophrenia. Also, exciting new studies show that niacin vitamin can fight against Alzheimer’s disease.

Keeping Skin Healthy

One of the benefits of taking niacin is having a glowing, healthy skin. Niacin can help protect against sun damage. This refers to B3 supplements taken orally as well as to lotions containing niacin. Exposure to dangerous UV rays is the main cause of skin cancer, but one study found out that a daily dose of 1 gram of niacin slashes the risks of developing the disease in people prone to it.

hand touching flowers

What Are the Side Effects of Niacin Supplements?

Experts consider niacin to be safe, but people taking vitamin B3 supplements should be aware of the potential side effects. The most common side effects are:

  • Skin flushing
  • Itchiness
  • Dizziness
  • Nausea
  • Rapid heartbeat
  • Vomiting or diarrhea

Skin flushing is a frequent side effect reported by people who take high doses of niacin (1 to 6 grams per day) to treat elevated blood pressure. It’s not a life-threatening condition, but it can be very unpleasant. Studies suggest that taking aspirin can reduce the intensity of hot flushes.

At the same time, high doses of niacin can cause liver toxicity, which is why people with a liver condition should avoid vitamin B3 supplements. Vitamin B3 niacin is also not recommended to pregnant women.

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The pace of modern life can make getting essential nutrients for eye health difficult. But plant-based vision health supplements like SightC can help.

Informed by the wisdom of Traditional Chinese Medicine and backed by science, SightC is a full-spectrum eye health supplement rich in antioxidants, beta-carotene, lutein, and other phytonutrients. Alongside niacin, these play a key role in sustaining the health of your eyes.

Learn more about SightC and how it can protect your eyes.