什麼是菸鹼醯胺?用途和副作用

What is nicotinamide

Nicotinamide is a form of niacin or vitamin B3. When consumed and absorbed by the body, B3 is converted into its main active form, nicotinamide adenine dinucleotide (NAD). NAD helps trigger reactions in the body involving cell communication, energy production, and many other critical functions.

Preventing niacin (B3) deficiency in certain cases

Most people get enough niacin through diet alone. Your body can convert small amounts of the amino acid tryptophan into NAD, so tryptophan in foods like chicken, fish, eggs, and seeds are considered dietary sources of niacin. However, some people may need to supplement with niacinamide if they are unable to obtain sufficient niacin through food.

Certain populations are more susceptible to niacin deficiency due to insufficient dietary intake of niacin, tryptophan, and other nutrients involved in the conversion of tryptophan to niacin. If left untreated, niacin deficiency can lead to pellagra, a disease that causes dermatitis, dementia, diarrhea, and can even lead to death.

People with alcohol use disorders, Crohn's disease, anorexia, carcinoid syndrome, and HIV/AIDS are often malnourished, which may lead to niacin deficiency. People who live in poverty and lack consistent access to food may also develop niacin deficiency due to a lack of proper nutrition.

Additionally, people with Hartnap disease, a rare genetic disorder, rely on niacin supplements because their bodies lack the ability to absorb certain amino acids from their diet, which can lead to low nutritional levels, including Low niacin levels.

People who do not get enough niacin, tryptophan, and other nutrients needed to produce niacin in the body in their diet need niacin supplements, such as niacinamide, to maintain healthy niacin levels.

Uses in skin care

Nicotinamide is popular in skin care products due to its many beneficial effects on the skin. Here are some of the key characteristics of nicotinamide:

  • Skin Barrier Function: Nicotinamide helps enhance the skin’s barrier function. It improves the overall integrity of the skin barrier, making it more resistant to environmental stressors and reducing moisture loss.
  • Moisturizing: Nicotinamide has moisturizing properties that help keep skin hydrated. It is often included in formulas for dry or dehydrated skin.
  • Anti-Inflammatory: Nicotinamide has anti-inflammatory properties and is suitable for people with sensitive or inflamed skin. It may help reduce redness and soothe irritated skin.
  • Reduces Pigmentation: Niacinamide is known to help reduce the appearance of pigmentation, such as dark spots, sun spots, and melasma. It inhibits the transfer of pigment within the skin and may help make skin tone more even.
  • Regulates sebum production: Nicotinamide has been shown to regulate sebum (oil) production, making it beneficial for people with oily or acne-prone skin. It helps maintain balance without over-drying the skin.
  • Antioxidant properties: Nicotinamide has antioxidant properties, which means it can help protect the skin from oxidative stress caused by free radicals. This helps prevent premature aging.
  • Reduces wrinkles: Some research suggests that nicotinamide may have anti-aging effects, including reducing fine lines and wrinkles. It is thought to stimulate the production of collagen, which is essential for skin elasticity.
  • Compatibility: Nicotinamide is generally well tolerated by most skin types, including sensitive skin. It is less likely to cause irritation than some other active ingredients commonly used in skin care products.

Nicotinamide is a versatile ingredient commonly found in a variety of skin care products, including moisturizers, serums, and creams. Due to its many benefits, it can be incorporated into your daily skin care routine. However, as with any skin care ingredient, it is recommended to patch test new products to ensure compatibility with individual skin types.

Other uses

Can prevent skin cancer

Some evidence suggests that niacinamide supplementation may help reduce the risk of skin cancer recurrence in certain groups.

One study of people with non-melanoma skin cancer found that participants who supplemented with 500 mg of nicotinamide daily for a year had a reduced risk of developing skin cancer. They also had a reduced risk of developing precancerous skin spots compared with the placebo group.

Research has found that nicotinamide supplements significantly reduce the occurrence of new skin cancers in healthy people and organ transplant recipients.

Nicotinamide may help prevent skin cancer by preventing UV-related cell damage, boosting cellular energy, and enhancing DNA repair. It also helps prevent immune suppression often caused by sun damage.

Helps prevent high levels of phosphorus in dialysis patients

Nicotinamide supplements can help people with end-stage kidney disease break down phosphorus, helping to lower phosphorus levels in the blood.

Nicotinamide is safe and effective in reducing phosphorus levels in hemodialysis patients. Researchers also found that niacinamide supplementation helped increase cardioprotective HDL cholesterol in this group.

However, nicotinamide may increase the risk of thrombocytopenia, or low platelet levels, in people with end-stage renal disease, which may have negative health effects.

Can improve acne

Nicotinamide supplements have been shown to be helpful for acne sufferers.

Studies have found that nicotinic acid supplements can significantly reduce acne.

Nicotinamide has powerful anti-inflammatory effects and may help reduce acne symptoms.

Although oral nicotinamide may be effective in reducing some acne symptoms, current evidence is limited, and most studies examining the effects of nicotinamide on acne severity have focused on topical treatments rather than oral treatments.

Does not cause skin flushing

Some forms of vitamin B3 supplements can cause skin flushing when taken in large doses.

When taken in doses of 1,000 to 3,000 mg per day, niacin can cause a flushing reaction, characterized by redness and sometimes itching of the skin. This reaction is related to its crystalline nicotinic acid component.

Nicotinamide has a different chemical structure than niacin and does not cause the same adverse reactions when taken in large doses.

Can protect the eye health of glaucoma patients

Glaucoma is a group of eye diseases that can cause blindness due to damage to the optic nerve. Nicotinamide can help improve eye function and vision in glaucoma patients by preventing nerve damage and enhancing cell health.

The study found that participants with glaucoma who took nicotinamide experienced improvements in inner retinal function and vision.

Glaucoma causes vision loss by damaging retinal ganglion cells (RGCs), the nerve cells responsible for sending visual stimuli to the brain. Nicotinamide may help protect these cells from degeneration caused by glaucoma, which may help prevent vision loss.

How to take niacinamide

Nicotinamide is available in capsule, tablet, powder, and liquid supplement forms.

Nicotinamide can be taken as a stand-alone supplement or combined with other nutrients.

Nicotinamide is usually recommended to be taken with food and is usually divided into multiple doses per day.

dose

Many niacinamide supplements contain 500 mg or more of niacinamide per serving. Most studies investigating the health effects of nicotinamide have used doses ranging from 500 mg to 3,000 mg per day.

However, it is usually not necessary to take very high doses of niacinamide. Even for people with niacin deficiency, a dose of 500 mg per day is usually enough to increase niacin levels in the body.

Unless prescribed by your doctor, you should generally avoid taking high-dose nicotinamide supplements, such as those that provide more than 500 mg per day.

Is nicotinamide safe?

Yes, nicotinamide is generally considered safe for topical use in skin care products. It is well tolerated by most people and suitable for a variety of skin types, including sensitive skin. The safety of nicotinamide has been extensively studied, and adverse effects are rare.

Here are some reasons why nicotinamide is considered safe:

Low Irritation Potential: Nicotinamide is known for being gentle on the skin. Unlike some other active ingredients, it's less likely to cause irritation, redness, or sensitivity.

Stability: Nicotinamide is stable and not easily degraded when exposed to light or air. This stability makes it a reliable ingredient in skin care formulas.

Compatibility: Nicotinamide is compatible with a variety of other skin care ingredients, making it suitable for inclusion in a variety of formulas, such as creams, serums, and lotions.

Well Tolerated: Many people can use nicotinamide without adverse effects. It is usually recommended for people with sensitive skin or conditions such as rosacea.

Non-comedogenic: Nicotinamide is non-comedogenic, which means it won’t clog pores. This makes it suitable for people with acne-prone skin.

It's important to note that while niacinamide is generally safe when used topically, some people may still experience allergic reactions or irritation. As with any skin care product, patch testing is recommended before using new products containing niacinamide, especially if you have sensitive skin or a known allergy.

If you have a specific concern or skin condition, it's best to consult a dermatologist or skin care professional before introducing new products into your daily routine. They can provide personalized recommendations based on the unique needs and characteristics of your skin.

Potential drug interactions

Nicotinamide may interact with the following drugs:

  • Carbamazepine (Tegretol): Taking niacinamide may increase levels of the anti-epileptic drug carbamazepine by reducing how quickly your body breaks down carbamazepine.
  • Blood thinners: Nicotinamide may slow down the body's ability to clot blood, which may enhance the anticoagulant effects of blood-thinning drugs such as warfarin (Coumadin).
  • Primidone (Mysoline): Primidone is an epilepsy medication. Nicotinamide may slow down the body's ability to break down this medication, which may affect how the medication works.

In addition to medications, niacinamide may interact with certain herbs, such as those with blood-thinning properties, such as ginger and ginseng. Therefore, use caution when taking niacinamide with other dietary supplements, especially those containing herbal ingredients.

If you are taking any medications or supplements, consult your healthcare provider before taking niacinamide.

Can you overdose on niacinamide?

Nicotinamide supplements are safe when taken appropriately. However, if you take too high a dose, it may cause unwanted side effects.

For example, nicotinamide may cause symptoms such as stomach upset, dizziness, and rashes, and may cause liver toxicity if taken in high doses of more than 3 grams per day.

Children should not exceed the tolerable upper intake (UL) for their age group. The UL values ​​for niacinamide for children aged 1 to 18 years are as follows:

age Daily UL
1-3 years 10 mg
4-8 years old 15 mg
9-13 years old 20 mg
14-18 years old 30 mg

People who are pregnant or breastfeeding and over 18 years of age should not consume more than 35 mg of niacinamide per day.

Nicotinamide side effects

Nicotinamide has fewer side effects than other forms of nicotinic acid (B3) (nicotinic acid).

However, when taken in high doses, nicotinamide may cause the following side effects:

  • nausea
  • Vomit
  • gas
  • upset stomach
  • Headache
  • fatigue
  • Dizziness
  • rash

In severe cases, high concentrations of niacinamide or niacin can cause hepatotoxicity.

If you are taking niacinamide and experience any of these side effects, stop taking the supplement and contact your healthcare provider for advice.

Review

All comments are moderated before being published