Chris Masterjohn PhD talks about Niacin Part 2: Blood Tests, Foods, and Supplements

Chris Masterjohn PhD talks about Niacin Part 2: Blood Tests, Foods, and Supplements

In part 1 we covered what niacin is and why you need it. Here’s part 2, where Alex Leaf and I cover blood tests, foods, and supplements!

  • How much do we need? The RDA has some flaws, including claiming women need less than men, when all the evidence shows women need *more* than men.
  • Why eating enough protein is so essential, yet so unreliable as a way of boosting niacin status.
  • How the niacin in your coffee, seeds, and grains is all locked up and unavailable, and how to release it through proper preparation. Do you drink light roast or dark roast? You may either hate or love this episode… or you might just switch coffees.Should we take high-dose niacin to lower cholesterol? Alex has a theory on how we can do that without getting diabetes.  😬
  • High-dose niacin can cause liver failure and can kill lab mice. But Alex and I know how to steer clear of that problem!
  • NAD-boosting supplements are the new darling of the anti-aging industry. But should we take nicotinamide riboside (NR), nicotinamide mononucleotide (NMN), or should we endure all the whole-body burning🔥 that the folks injecting NAD+ are so hyped up about? We discuss the promises and problems of these approaches.
  • Why you should match glycine to one form of niacin and trimethylglycine (TMG) to all of them.

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Niacin Part 2 Show Notes

00:38 Cliff Notes

01:35 Recap of Part 1

15:32 Markers of niacin status

17:32 Methylated metabolites of niacin in the urine as a marker of niacin status

19:05 Caveat to using methylated metabolites of niacin in the urine as a marker of niacin status

20:16 Erythrocyte NAD(H)/NADP(H) ratio, the “niacin number,” as a marker of niacin status

22:55 Caveat to the niacin number as a marker of niacin status

28:34 Critique on how the RDA for niacin was established

40:12 How protein intake affects the dietary requirement for preformed niacin

42:48 Estrogen regulates the synthesis of niacin from tryptophan.

43:35 In men in particular, niacin synthesis from tryptophan might just be a way to clear excess tryptophan.

45:31 General discussion about protein requirements

49:46 How different forms of food processing, such as nixtamalization, fermentation, and sprouting, increase the bioavailability of niacin

52:51 Niacin in coffee

53:52 Niacin in nutritional yeast

54:16 Dietary sources of niacin, divided into five tiers

59:57 Niacin in herbs and spices, including spirulina

01:03:46 The contribution of the microbiome to niacin status is not well studied.

01:04:56 Where we would expect to see niacin deficiency

1:05:38 Risk factors for niacin deficiency include Hartnup’s disease, megaduodenum, intestinal malabsorption, carcinoid tumors, certain drugs, alcoholism, HIV/AIDS, and deficiencies of iron, riboflavin, and B6.

01:09:52 Risk factors for suboptimal niacin status include a diet based on unprocessed whole grains, a diet based on sugar and fat, a diet low in non-collagen protein, any form of cellular damage, and low ATP levels.

01:14:42 How metformin and berberine could affect niacin status

01:17:28 The effect of leucine and muscle growth on niacin status

01:19:54 The prevalence of inadequate niacin intake and niacin deficiency

01:24:00 Contributors to niacin toxicity

01:25:08 The use of nicotinic acid to benefit blood lipids and reduce heart disease risk

01:31:14 Potential side effects of taking nicotinic acid to manage blood lipids include the flushing reaction, liver harm, and increased diabetes risk.

01:34:22 The mechanism behind high-dose nicotinic acid-induced insulin resistance and how you could mitigate it

01:48:01 Rodent studies of nicotinamide riboside supplementation

01:50:58 Human studies of nicotinamide riboside supplementation

01:56:32 Why the rodent studies of nicotinamide riboside supplementation look more promising than the human studies

02:04:16 What is the probability that someone would get longevity benefits from supplementing with nicotinamide riboside?

02:05:15 Whether or not Alex and Chris will start supplementing with niacin after doing the research for this podcast

02:06:17 Should someone with hypercholesterolemia consider taking nicotinic acid? How should they manage the side effects, and which form is best?

02:10:53 Does it matter if niacin is taken with food?

Niacin Links and Research

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  1. I’m totally confused. Niacin is bad for those with fatty liver/diabetes, but then you say you need it for diabetes — for methylation — and then you started to mention quinolinate, but didn’t finish that part of the discussion.

    Is it just high-dose niacin that’s bad for fatty liver/insulin resistance? And would one take low-dose niacine to prevent elevated quinolinic acid?

    1. And then if there’s not enough ATP, then it gets converted to niacinamide, “which you do not want”???

      Help please…

  2. So you don’t believe NR supplements such as Thorne’s Resveracel provide any appreciable benefits that justify their consumption?

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