Short Answer: Plasma zinc is the single most important marker of zinc status. Urine zinc may decline faster in deficiency. Hair zinc increases with supplementation but does not decrease in deficiency. Plasma zinc is decreased by inflammation, oxidative stress, the ovulatory and luteal phases of the menstrual cycle, probably pregnancy and oral contraceptive use, and any kind of stress that leads to an adrenal output. If plasma zinc declines despite supplementation, corroborate that this reflects zinc status by showing normal hair zinc and low urine zinc. Use symptoms as the ultimate arbiter of whether zinc supplementation is helping. This is a clip from a live Q&A session open to CMJ Masterpass members. In addition to this episode, you can access two other free samples using this link: https://chrismasterjohnphd.substack.com/p/questions-on-statins-versus-sulfur In that batch of free episodes you will also find the answers to these questions: Statins Vs. Sulfur for Heart Disease Glutathione Intolerance: Getting to the Bottom of It If you want to become a Masterpass member so you can participate in the next live Q&A, or so you can have access to the complete recording and transcript of each Q&A session, you can save 10% off the subscription price for as long as you remain a member by using this link to sign up: https://chrismasterjohnphd.substack.com/qanda Learn more about the Masterpass here: https://chrismasterjohnphd.substack.com/about This snippet is from the October 12, 2022 AMA. The full recording and transcript is reserved for Masterpass members. Here is a preview of what’s included: NADH vs NMN vs NR An unexplained rise in urine ketones Spreading out calcium across meals What should we have in our cold season cabinet? What besides diet could cause my high morning glucose on a CGM? Will some older people benefit from supplementing carnitine? What do I think about the CGM fad? Could my low triglycerides be cholestasis? Why limit the dose of cod liver oil? Why do I always feel better when my sulfur problems are worse? Should I use one lab’s reference range with another lab’s results? Is it safe to eat roasted potatoes? How much weight should I give genetic SNPs in my nutrition? High RBC magnesium but low serum: what could it mean? Burning in the stomach: what could it be? Should I treat low plasma amino acids by supplementing them? Why would MK-4 cause heart palpitations? Here’s a link to the full AMA: https://chrismasterjohnphd.substack.com/p/recording-and-transcript-of-the-october  Access the show notes, transcript, and comments here.

Explore the causes of glutathione intolerance and learn about various hypotheses and tests to determine the factors contributing to it. Delve into the breakdown and synthesis of glutathione, as well as the metabolism of cysteine. Discover the potential toxic by-products associated with different options for metabolizing cysteine and find out about recommended interventions for glutathione intolerance.

Short Answer: From the trials, statins seem to reduce heart disease risk and total mortality, but it is impossible to separate this from conflicts of interest and industry funding. There are plausible mechanisms by which they may hurt mitochondrial function and promote soft tissue calcification. Dietary sulfur appears to lower cholesterol. While Lester Morrison showed 1500 milligrams per day of chondroitin sulfate could reduce cardiac events 7-fold, this has a theoretical potential to hurt the microbiome. My preferred way of getting sulfur is 1.2-1.8 grams per kilogram bodyweight of total non-collagen protein, with an emphasis on animal protein. This is a clip from a live Q&A session open to CMJ Masterpass members. In addition to this episode, you can access two other free samples using this link: https://chrismasterjohnphd.substack.com/p/questions-on-statins-versus-sulfur In that batch of free episodes you will also find the answers to these questions: Glutathione Intolerance: Getting to the Bottom of It Why Plasma Zinc is the Best Marker of Zinc Status If you want to become a Masterpass member so you can participate in the next live Q&A, or so you can have access to the complete recording and transcript of each Q&A session, you can save 10% off the subscription price for as long as you remain a member by using this link to sign up: https://chrismasterjohnphd.substack.com/qanda Learn more about the Masterpass here: https://chrismasterjohnphd.substack.com/about This snippet is from the October 12, 2022 AMA. The full recording and transcript is reserved for Masterpass members. Here is a preview of what’s included: NADH vs NMN vs NR An unexplained rise in urine ketones Spreading out calcium across meals What should we have in our cold season cabinet? What besides diet could cause my high morning glucose on a CGM? Will some older people benefit from supplementing carnitine? What do I think about the CGM fad? Could my low triglycerides be cholestasis? Why limit the dose of cod liver oil? Why do I always feel better when my sulfur problems are worse? Should I use one lab’s reference range with another lab’s results? Is it safe to eat roasted potatoes? How much weight should I give genetic SNPs in my nutrition? High RBC magnesium but low serum: what could it mean? Burning in the stomach: what could it be? Should I treat low plasma amino acids by supplementing them? Why would MK-4 cause heart palpitations? Here’s a link to the full AMA: https://chrismasterjohnphd.substack.com/p/recording-and-transcript-of-the-october Access the show notes, transcript, and comments here.

Short Answer: I believe most methyl donor intolerances are a result of deficiencies in the glycine buffer system, which requires glycine, vitamin A, fasting (glucagon), androgens, riboflavin, unmethylated folate (THF), and iron. No one should expect to tolerate 30 milligrams of folate, however, and there is almost never a reason to use doses that high. This is a clip from a live Q&A session open to CMJ Masterpass members. In addition to this episode, you can access two other free samples using this link: https://chrismasterjohnphd.substack.com/p/questions-on-cognitive-health-mct In that batch of free episodes you will also find the answers to these questions: Does whey protein hurt the kidneys or otherwise hurt our health Why would someone not tolerate methyl donors even if they need them? If you want to become a Masterpass member so you can participate in the next live Q&A, or so you can have access to the complete recording and transcript of each Q&A session, you can save 10% off the subscription price for as long as you remain a member by using this link to sign up: https://chrismasterjohnphd.substack.com/qanda Learn more about the Masterpass here: https://chrismasterjohnphd.substack.com/about This snippet is from the September 14, 2022 AMA. The full recording and transcript is reserved for Masterpass members. Here is a preview of what’s included: Why isn't my ferritin as high as diabetics when my transferrin saturation is higher? Why are vitamins A and E needed alongside D and K? Sunflower lecithin versus phosphatidylcholine supplements How do I reduce congestion while consuming dairy? Could eggs be raising triglycerides by curing fatty liver? Why would homocysteine ever be high when you can just use it to make glutathione? Why did my eye start twitching after sweating more than usual this weekend? Why do I now think A and D should be in roughly 1:1 ratios? Would MK-7 be enough to take with D or do I need MK-4? Why does water make me hungry? What's the proper ratio of calcium to magnesium, vitamin D, and vitamin K2? Is it safe to take zinc carnosine long term? Why did I recommend only using high-dose zinc for COVID protection for one year? Why did I recommend limiting quercetin phytosome to three months? Why take MK-4 when it has such a short half-life? How to make bowel movements more regular? Could freeze dried animal beef supplements cause gut infections? Do I recommend food sensitivity testing? What are the nutritional causes of restless leg syndrome? What do I think of drinking deuterium-depleted water for COVID severity? Here’s a link to the full AMA: https://chrismasterjohnphd.substack.com/p/recording-and-transcript-of-the-september Access the show notes, transcript, and comments here.

Short Answer: The main problem with too much protein, particularly animal protein, is that acidity may hurt the bones and increase the risk of calcium oxalate kidney stones, but this can be obviated by balancing it with organic acids, which have bicarbonate-sparing effects that are alkalinizing. The best index of the organic acid content of foods is the potassium content. This balance can be achieved with 750 to 1500 milligrams of potassium for every 100 grams of protein. This is not specific to whey protein. Other than allergies, none of the claimed harms of whey protein are convincing. This is a clip from a live Q&A session open to CMJ Masterpass members. In addition to this episode, you can access two other free samples using this link: https://chrismasterjohnphd.substack.com/p/questions-on-cognitive-health-mct In that batch of free episodes you will also find the answers to these questions: Does glucose handling in the brain decline with age? And if so, does this serve as a rationale to supplement with MCT oil to prevent cognitive decline? Why would someone not tolerate methyl donors even if they need them? If you want to become a Masterpass member so you can participate in the next live Q&A, or so you can have access to the complete recording and transcript of each Q&A session, you can save 10% off the subscription price for as long as you remain a member by using this link to sign up: https://chrismasterjohnphd.substack.com/qanda Learn more about the Masterpass here: https://chrismasterjohnphd.substack.com/about This snippet is from the September 14, 2022 AMA. The full recording and transcript is reserved for Masterpass members. Here is a preview of what’s included: Why isn't my ferritin as high as diabetics when my transferrin saturation is higher? Why are vitamins A and E needed alongside D and K? Sunflower lecithin versus phosphatidylcholine supplements How do I reduce congestion while consuming dairy? Could eggs be raising triglycerides by curing fatty liver? Why would homocysteine ever be high when you can just use it to make glutathione? Why did my eye start twitching after sweating more than usual this weekend? Why do I now think A and D should be in roughly 1:1 ratios? Would MK-7 be enough to take with D or do I need MK-4? Why does water make me hungry? What's the proper ratio of calcium to magnesium, vitamin D, and vitamin K2? Is it safe to take zinc carnosine long term? Why did I recommend only using high-dose zinc for COVID protection for one year? Why did I recommend limiting quercetin phytosome to three months? Why take MK-4 when it has such a short half-life? How to make bowel movements more regular? Could freeze dried animal beef supplements cause gut infections? Do I recommend food sensitivity testing? What are the nutritional causes of restless leg syndrome? What do I think of drinking deuterium-depleted water for COVID severity? Here’s a link to the full AMA: https://chrismasterjohnphd.substack.com/p/recording-and-transcript-of-the-september Access the show notes, transcript, and comments here.

High-dose biotin supplements can cause a multitude of false lab tests, masking recent heart attacks, pregnancies, or allergies, giving false signals about tumors, and far more. In this episode, I lay out for you the nature, scope, and magnitude of the problem, and develop actionable strategies you can use to protect your lab tests from generating false information as a result of this phenomenon. You can find the written and fully referenced version of this episode here: https://chrismasterjohnphd.substack.com/p/biotin-causes-false-lab-tests The written version also contains some figures that help you visualize the mechanistic information. If you find this episode valuable, please head over to the written version on Substack using the above link to like it, share it, and comment on it. This will encourage the Substack algorithm to get it in front of more people. In High Protein? You Need More Biotin, I made the case that 30 micrograms per day is not enough for adults, and that many people need 150-300 micrograms per day, depending on how much protein they eat. My simple food-based recommendations for getting enough biotin are found in my Cliff Notes (free for Masterpass members here). To learn more about the Masterpass, click here. Stay Immune Through the Winter My new 7-page quick guide on how to not get sick this winter, Staying Immune Through the Winter, is free for everyone. All you need is a free or paid subscription to my Substack. Head here to check your subscription status and to make sure you get the guide: Staying Immune Through the Winter Join the Next Live Q&A Have a question for me? Ask it at the next Q&A! Learn more here. Join the Masterpass Masterpass members get access to premium content (preview the premium posts here), all my ebook guides for free (see the collection of ebook guides here), monthly live Q&A sessions (see when the next session is here), all my courses for free (see the collection here), and exclusive access to massive discounts (see the specific discounts available by clicking here). Upgrade your subscription to include Masterpass membership with this button: Join the Masterpass Learn more about the Masterpass here.

Short Answer: Energy metabolism in general declines across the body with aging, but energy metabolism seems to stay healthy enough in the brain in people who do not experience cognitive decline. Cognitive decline does appear to be driven by decreases in brain energy metabolism, but these are not best described as a specific impairment in glucose handling. MCT oil can be modestly beneficial and a ketogenic diet can probably be somewhat more beneficial in people who have cognitive decline from any type. There is no evidence to support using it as a preventative. For prevention, I believe we should focus on aerobic fitness, nutrients required for healthy energy metabolism and antioxidant defense, and maintaining metabolic health with a healthy body composition and a healthy physical activity routine that includes the proper spread of a portfolio of different types of exercise. This is a clip from a live Q&A session open to CMJ Masterpass members. In addition to this episode, you can access two other free samples using this link: https://chrismasterjohnphd.substack.com/p/questions-on-cognitive-health-mct In that batch of free episodes you will also find the answers to these questions: Does whey protein hurt the kidneys or otherwise hurt our health Why would someone not tolerate methyl donors even if they need them? If you want to become a Masterpass member so you can participate in the next live Q&A, or so you can have access to the complete recording and transcript of each Q&A session, you can save 10% off the subscription price for as long as you remain a member by using this link to sign up: https://chrismasterjohnphd.substack.com/qanda Learn more about the Masterpass here: https://chrismasterjohnphd.substack.com/about This snippet is from the September 14, 2022 AMA. The full recording and transcript is reserved for Masterpass members. Here is a preview of what’s included: Why isn't my ferritin as high as diabetics when my transferrin saturation is higher? Why are vitamins A and E needed alongside D and K? Sunflower lecithin versus phosphatidylcholine supplements How do I reduce congestion while consuming dairy? Could eggs be raising triglycerides by curing fatty liver? Why would homocysteine ever be high when you can just use it to make glutathione? Why did my eye start twitching after sweating more than usual this weekend? Why do I now think A and D should be in roughly 1:1 ratios? Would MK-7 be enough to take with D or do I need MK-4? Why does water make me hungry? What's the proper ratio of calcium to magnesium, vitamin D, and vitamin K2? Is it safe to take zinc carnosine long term? Why did I recommend only using high-dose zinc for COVID protection for one year? Why did I recommend limiting quercetin phytosome to three months? Why take MK-4 when it has such a short half-life? How to make bowel movements more regular? Could freeze dried animal beef supplements cause gut infections? Do I recommend food sensitivity testing? What are the nutritional causes of restless leg syndrome? What do I think of drinking deuterium-depleted water for COVID severity? Here’s a link to the full AMA: https://chrismasterjohnphd.substack.com/p/recording-and-transcript-of-the-september Access the show notes, transcript, and comments here.  

Short Answer: If it can’t be explained by the dose of salt, it may be that the salt is not being absorbed orally. Glucose, starch, or simply a meal consumed alongside the salted water may help with this. This is a clip from a live Q&A session open to CMJ Masterpass members. In addition to this episode, you can access two other free samples using this link:   https://chrismasterjohnphd.substack.com/p/questions-on-protein-and-longevity-1a2 In that batch of free episodes you will also find the answers to these questions: Protein and Longevity How to Increase or Decrease SHBG? If you want to become a Masterpass member so you can participate in the next live Q&A, or so you can have access to the complete recording and transcript of each Q&A session, you can save 10% off the subscription price for as long as you remain a member by using this link to sign up: https://chrismasterjohnphd.substack.com/qanda Learn more about the Masterpass here: https://chrismasterjohnphd.substack.com/about This snippet is from the August 15, 2022 AMA. The full recording and transcript is reserved for Masterpass members. Here is a preview of what’s included: Does which food you eat matter when everything is digested anyway? How to know if your nitric oxide is dilating your blood vessels properly? How big of a problem are transient glucose spikes above 140 mg/dL? Can I take too much collagen? What is the maximum dose of cod liver oil safe to use long-term? How much A is safe to take when I need so much to resolve my symptoms? Generalizing from cell studies of green tea catechins to cups of green tea per day. What to do about lumbar discs bulging? Why would vitamin K2 cause a nosebleed? How to balance A with D when I react poorly to D and need so much A? Why would COVID decrease HRV long-term? How to raise secretory IgA? Rapid-fire answers to pre-submitted questions that didn’t win the contest: alternatives to bone meal powder, herbal tea and nutrient absorption, retinol-binding protein, improving fat digestion, metal provocation tests, fatty liver, high-dose B vitamins, eyebrow thinning, itchy bumps after exercise, brain fog and rifaximin, low cholesterol, tolerating chlorine pools, cycling nutrients, copper toxicity, stopping supplements before blood tests, COVID vaccines causing post-nasal drip, natural vs synthetic vitamins, absorbing iron through baths, elevated EPA and DHA in RBCs, COVID affecting the vagus nerve, supplements for athletic performance, when water doesn’t hydrate, tics and Tourette’s, recalcitrant homocysteine, fraud and corruption in scienctific research. Here’s a link to the full AMA: https://chrismasterjohnphd.substack.com/p/recording-and-transcript-of-the-august Access the show notes, transcript, and comments here.

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Short Answer: SHBG is increased by adiponectin (vitamin K2, insulin sensitivity), thyroid hormone, fasting physiology (AMPK, fat oxidation), and estrogen (especially estrone), while it is decreased by insulin resistance, obesity, the fed state and carbohydrate-dominant physiology, androgens, and polyunsaturated fat. This is a clip from a live Q&A session open to CMJ Masterpass members. In addition to this episode, you can access two other free samples using this link:   https://chrismasterjohnphd.substack.com/p/questions-on-protein-and-longevity-1a2 In that batch of free episodes you will also find the answers to these questions: Protein and Longevity  Why is an IV more hydrating than salted water? If you want to become a Masterpass member so you can participate in the next live Q&A, or so you can have access to the complete recording and transcript of each Q&A session, you can save 10% off the subscription price for as long as you remain a member by using this link to sign up: https://chrismasterjohnphd.substack.com/qanda Learn more about the Masterpass here: https://chrismasterjohnphd.substack.com/about This snippet is from the August 15, 2022 AMA. The full recording and transcript is reserved for Masterpass members. Here is a preview of what’s included: Does which food you eat matter when everything is digested anyway? How to know if your nitric oxide is dilating your blood vessels properly? How big of a problem are transient glucose spikes above 140 mg/dL? Can I take too much collagen? What is the maximum dose of cod liver oil safe to use long-term? How much A is safe to take when I need so much to resolve my symptoms? Generalizing from cell studies of green tea catechins to cups of green tea per day. What to do about lumbar discs bulging? Why would vitamin K2 cause a nosebleed? How to balance A with D when I react poorly to D and need so much A? Why would COVID decrease HRV long-term? How to raise secretory IgA? Rapid-fire answers to pre-submitted questions that didn’t win the contest: alternatives to bone meal powder, herbal tea and nutrient absorption, retinol-binding protein, improving fat digestion, metal provocation tests, fatty liver, high-dose B vitamins, eyebrow thinning, itchy bumps after exercise, brain fog and rifaximin, low cholesterol, tolerating chlorine pools, cycling nutrients, copper toxicity, stopping supplements before blood tests, COVID vaccines causing post-nasal drip, natural vs synthetic vitamins, absorbing iron through baths, elevated EPA and DHA in RBCs, COVID affecting the vagus nerve, supplements for athletic performance, when water doesn’t hydrate, tics and Tourette’s, recalcitrant homocysteine, fraud and corruption in scienctific research. Here’s a link to the full AMA: https://chrismasterjohnphd.substack.com/p/recording-and-transcript-of-the-august Access the show notes, transcript, and comments here.