Vitamin B3 (Niacin) plays a role in energy metabolism, acts as natural antidepressant, and provides antioxidant properties

pellagra-n

Vitamin B3 or Niacin is one of the 9 water soluble vitamins. Deficiency in vitamin B3 at one time caused over 100,000 deaths (due to Pellagra disease stemmed from Niacin deficiency) in the United States from 1900-1940. At the time, they diagnosed the cause of death as “infection” because Pellagra does have signs of severe infection. Back then, most victims were poor people or those from the South where foods were not treated as a necessity but a condiment with the focus on good taste while sacrificing nutrient (diets heavy on empty calories from fat and sugar). It’s not until 1938 when the U.S mandated Niacin enrichment in flour products. Since then, this country does not face another Vitamin B3 deficiency outbreak. However, in other countries, until the recent years, still suffer vitamin B3 deficiency.

1/ Functions of vitamin B3

Vitamin B3 plays significant roles in carbohydrate metabolism, lipid metabolism, and protein metabolism and providing NAD and NADP that behave as antioxidant. Therefore, vitamin B3 is not an antioxidant itself, but capable of producing enzymes that provide us health benefits of antioxidants. If you remember the blog about vitamin A, you’ll find some similarity between vitamin A and vitamin B3: they are both now antioxidants, but they provide substances that contain properties of antioxidants.

Vitamin B3 is the only vitamin that can store glycogen in liver and muscles. Glycogen is the source of energy preferred by the body over fat and protein energy. In animals, including human beings, glycogen can be stored in only 2 places: liver and muscles. I’ll talk more about glycogen when I write the blog about anatomy and exercise. For now, we just need to know that vitamin B3 deficiency may give us hard time working out.

Studies have shown that vitamin B3 can be considered as a complimentary treatment for people with depression when consumed at high dose.

Vitamin B3 can help lower total cholesterol level, which may be related to its role in lipid metabolism.

2/ Recommended daily intake:

  • 0-6 months: 2 mg/day
  • 7-12 months: 4 mg/day
  • 1-3 years: 6 mg/day
  • 4-8 years: 8 mg/day
  • 9-13 years: 12 mg/day
  • Males from 14 years: 16 mg/day
  • Females from 14 years: 14 mg/day
  • Pregnant women: 18 mg/day
  • Lactating women: 16 mg/day

3/ Deficiency: Signs and symptoms:

  • Dermatitis in hands and face
  • Heat flush in the face (unrelated to hormonal changes)
  • Lethargy
  • Loss of appetite
  • Anxiety
  • Depression

If deficiency is prolonged, it may cause Pellagra (rash will be everywhere), high cholesterol, acne,  mental confusion, dementia, and osteoathritis.

4/ Who’s at risk?

  • Alcoholics
  • People with sickle cell anemia
  • Vegan without proper nutrition
  • Those on restricted diet
  • People with anorexia
  • Those with conditions affecting the functions of digestive system: cancer, bariatric surgery, dialysis, liver diseases

5/ Toxicity:

It’s rare to get oneself toxic by consuming too much niacin from food. It’s observed that people can consume 160% of the recommended daily intake without toxicity, provided that the vitamin B3 comes from natural food sources. The upper limit for vitamin B3 is currently set at 35 mg per day without complications. However, for those who pop vitamin B3 supplements may be at risk of toxicity. When toxicity does occur, the signs include malfunction of liver, peptic ulcer and skin rash

6/ How do you obtain vitamin B3?

Well, as mentioned above, people with strict calories intake, those who puke after meals to control caloric intake, or vegetarians/vegans may have hard time getting enough vitamin B3. While plant based foods have some amount of vitamin B3, you must plan your meal well in order to get enough vitamin B3 if you must avoid meat consumption. The best source for vitamin B3 are chicken, turkey, tuna, and crimini mushroom. So, we see that vitamin B3 are available in large quantity in animal food source-that’s why vegan and vegetarians may be greater risk of vitamin B3 deficiency than other population (along with vitamin B12 deficiency). However, vegans and vegetarians can obtain niacin if they do plan their meals well: eating a large quantity of sweet potato, crimini mushroom, bell pepper, green beans and whole grains with added vitamin B3 (rice is not one of them-unfortunate for those in love with Asian cuisine) . All in all, I don’t see many people that can obtain vitamin B3 and other important nutrients with a diet below 1200 kcal (and I refuse to design a diet plan under 1200 calories unless they need to lose weight rapidly for medical reasons.)

  • 100 g chicken, roasted, braised, steamed: 13 mg vitamin B3
  • 100 g tuna (canned, grilled, baked, seared): 24 mg vitamin B3
  • 100g crimini mushrooms RAW or grilled: 3 mg
  • 100 g salmon (baked): 8.9 mg
  • 100 g beef (grilled): 7 mg
  • 100 g shrimp (grilled-no cocktail shrimp or boiled please): 2.9 mg
  • 100 g sweet potatoes (steamed, baked): 1.5 mg
  • 100 g summer squash or zucchini (steamed): 0.45 mg
  • 100 g green beans (steamed): 0.6 mg
  • 100 g bell pepper (raw, grilled, steamed): 0.9 mg
  • 100 g carrot (raw or steamed): 1.1 mg
  • 100 g spinach (raw or steamed): 0.45 mg
  • 100 g broccoli (raw or steamed): 0.58 mg
  • 100 g beet greens ( raw or steamed): 0.5 mg
  • 100 g bok choy (raw or steamed): 0.38 mg
  • 35 g roasted peanuts: 4.4 mg
  • 35 g raw sunflower seeds (or roasted) without shell: 2.9 mg

7/ How to retain vitamin B3 from foods?

Well, vitamin B3 is not sensitive to heat like vitamin B1. It’s also not sensitive to sun light either. So that’s a good thing. However, just like the rest of water soluble vitamins, rule of thumb stays the same: DO NOT, DO NOT, DO NOT let the food touch water. OR VITAMINS WILL LEAK INTO WATER. (unless you plan on drinking the veggie broth at the end of the meal then I guess it does not matter if you boil the food). However, the majority of us will discard the broth (tough to drink 1 liter of broth after a full meal, I suppose).

So the rule of avoiding water applies in all process of cooking and preparing. That means you should wash the veggies as whole before you chop it.

Also, studies have found that the use of a pressure cooker saves 90-95% of vitamins, whereas steaming will save about 75%. By boiling the food, you can lose up to 50% (actually depending on how long you boil it if the vitamins are heat sensitive type). Roasting and baking are certainly the bad way of cooking foods rich in heat-sensitive vitamins due to long cooking time. As always, if you deep fry your food, don’t bother estimate the nutrient you may obtain from it because it’s pretty much gone.

 

 

 

 

 

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