What is niacin of food nutrition fortifier?

What is niacin?
Niacin is a water-soluble vitamin, also known as vitamin B3, niacin is a general term for biologically active pyridine-3-carboxylic acid and its derivatives, and niacinamide is its main form in animals. Niacin has a simple chemical structure, stable physical and chemical properties, and is not easy to be destroyed by acid, alkali, and heat, so it is considered to be the most stable vitamin.
Physiological function of niacin
1. Participate in the metabolism of matter and energy in the body. Nicotinic acid forms Coenzyme I and Coenzyme II in the body in the form of nicotinamide, and the nicotinamide part of these two coenzyme structures has reversible hydrogenation and dehydrogenation properties and plays a role in the transfer of hydrogen during cellular biological oxidation.
2. Related to the synthesis of nucleic acids. Glucose can produce 5-phosphate ribose through the metabolic pathway of pentose phosphate, which is the main pathway of ribose production in the body, and ribose is an important raw material for the synthesis of nucleic acids. Coenzyme I and Coenzyme II composed of niacin are hydrogen transmitters in the first biochemical reaction of the glucose phosphate pentose metabolic pathway.
3. Lower blood cholesterol levels. Take 1-2g niacin daily to lower blood cholesterol levels. The principle may be that it interferes with the synthesis of cholesterol or lipoprotein, or that it promotes the synthesis of lipoprotein enzymes.
4. Components of glucose tolerance factor. Glucose tolerance factor (GTF) is a complex composed of trivalent chromium, niacin and glutathione. It may be a co-factor of insulin, which can increase the utilization of glucose and promote the conversion of glucose into fat.
Deficiency and excess
Although the content of niacin in corn is higher than that in rice, the niacin in corn is of the combined type, which is not easy to be absorbed and utilized by the human body, but the addition of alkali can make the combined type niacin into free type niacin, which is easy to be utilized by the body. For example, when occasionally making polenta, steamed bun, and pasted tortillas, adding baking soda to corn flour, the food made with corn flour is not only color, aroma, and taste good, but also the combination of niacin is easy to be absorbed and utilized by the human body.
(Note: Use a small amount of alkali! Alkalis are a formidable enemy of most vitamins. Vitamin B1, vitamin B2, and vitamin C are very sensitive to alkali and will be destroyed in an alkaline environment, affecting absorption. TB patients taking large amounts of the anti-tuberculosis drug isoniazid for a long time will affect the conversion of tryptophan to niacin, so it can also cause niacin deficiency.
When niacin is deficient, the synthesis of coenzyme I and Coenzyme II in the body is blocked, and certain physiological oxidation processes are obstructed, that is, vitamin B3 deficiency – scabies. The typical symptoms are dermatitis, diarrhea and dementia, the so-called “triple-D symptoms.” Dermatitis occurs in the exposed parts of the body, such as the cheeks, the backs of the hands and the backs of the feet, and is symmetrical. There is a clear boundary between the affected skin and the healthy skin, and most of them are sunspot-like changes, the skin becomes reddish brown, the epidermis is rough, descaling, pigmentation, and neck dermatitis is more common. The main symptoms of digestive tract were loss of appetite, dyspepsia and diarrhea. At the same time, erosion of oral mucosa and tongue and scarlet tongue may occur. Neuropsychiatric symptoms include depression, anxiety, memory loss, apathy and dementia, and some may appear mania and hallucinations. At the same time, muscle tremor, tendon reflex allergy or disappearance. Vitamin B3 deficiency often co-exists with vitamin B1 and B2 deficiencies.
The side effects of excessive intake of niacin are mainly manifested as skin redness, eye discomfort, nausea and vomiting, hyperuricemia and abnormal glucose tolerance, etc. Long-term large intake can cause liver damage.
Note: The nutritional status of the body can be evaluated by measuring the ratio of 2-pyridone/N-methylnicotinamide in urine, urine load test, the ratio of N-methylnicotinamide to creatinine and the content of NAD in red blood cells.
Reference intake and food source
The reference intake of niacin should take into account energy expenditure and protein intake. Niacin, in addition to being taken directly from food, can also be converted from tryptophan in the body, with an average of 60mg of tryptophan being converted to 1mg of niacin. Therefore, the reference intake of vitamin B3 in the diet should be expressed as niacin equivalent (NE).
Niacin equivalent (mgNE) = niacin (mg) +1/60 tryptophan (mg) reference intake of dietary vitamin B3 for Chinese residents, the RNI for adult males was 14mg NE/d, the RNI for females was 13mg NE/d, and the UL was 35mg NE/d.
Niacin is widely found in various animal and plant foods. Niacin is mainly present in plant foods, and niacinamide is mainly present in animal foods. Niacin and niacinamide are abundant in liver, kidney, lean poultry meat, fish, whole grains and nuts. Although the content of niacin in milk and eggs is low, the content of tryptophan is high, which can be converted into niacin in the body.
The use of niacin as a nutritional fortifier
According to the provisions of the “GB 14880 National Standard for Food Safety Standard for the use of Food nutrition fortifier”, niacin as a nutritional fortifier is allowed to use the following varieties, scope of use and usage: