Today, January 14, is the *last day* to get 30% off your entire order by entering masterjohn as the promo code at checkout when you make purchases on paleovalley.com. Thiamin, or vitamin B1, is central to both energy metabolism and antioxidant defense. While its deficiency causes many problems, out of all the B vitamins its deficiency is most neurological in nature, because energy metabolism of the brain becomes severely compromised, and because neurotransmitters derived from protein cannot be produced. In its most severe form, beriberi, it can cause loss of muscle control, twitching, muscles freezing into awkward positions, and seizures. Carbohydrates require twice as much thiamin as fat. This means, on the one hand, that high-carbohydrate diets increase the need for thiamin, and on the other hand, that people who are deficient in thiamin may have neurological symptoms that resolve when they go on a low-carbohydrate, high-fat diet. Thiamin is widely distributed in foods. Historically, diets high in refined grain produced beriberi, but now refined grains are enriched in thiamin, so its deficiency is rarely caused by diet. However, certain foods such as raw fish and moths that are eaten in some cultures contain thiamin antagonists, gastrointestinal microbes can degrade thiamin, and there are various environmental causes of thiamin deficiency, such the algae that grow in dead zones. As such, environmental exposure to thiamin antagonists may be a more common cause of thiamin deficiency than poor dietary intake. Still, some foods are much higher in thiamin than most others, with whole grains, legumes, yeast, and red meat being among the best sources. The show notes for this episode are available at chrismasterjohnphd.com/50. This episode is brought to you by Testing Nutritional Status: The Ultimate Cheat Sheet. I wrote this to make everything you could possibly need to measure and manage your nutritional status all one click away. Get it now! This episode is brought to you by Paleovalley. I use their beef sticks as a convenient yet nutritious snack. They are made from 100% grass-fed beef and preserved through traditional fermentation. The fermentation makes them more digestible and gives them a fresher mouthfeel and texture compared to most other meat snacks I’ve tried, which tend to be too dry for me to fully enjoy. They also have a grass-fed organ complex that contains a blend of liver, heart, kidney, and brain, all stuffed into gel caps for those who can’t bring themselves to eat these incredibly nutritious meats with a fork. Head to paleovalley.com and enter the promo code masterjohn at checkout for 30% off your order. This is a huge savings available for only a limited time. You can get 30% off everything on the site, ordering as much as you want, but only for the duration of the next three podcast episodes. Check it out now to make sure you get your discount! This episode is brought to you by US Wellness Meats. I use their liverwurst as a convenient way to make a sustainable habit of eating a diversity of organ meats. They also have a milder braunschweiger and an even milder head cheese that gives you similar benefits, as well as a wide array of other meat products, all from animals raised on pasture. Head to grasslandbeef.com and enter promo code “Chris” at checkout to get a 15% discount on any order that is at least 7 pounds and is at least $75 after applying the discount but under 40 pounds (it can be 39.99 lbs, but not 40). You can use this discount code not once, but twice! To get these episodes free of ads, with transcripts, and weeks or sometimes even months before they are released to the public, along with access to monthly live Q&A sessions, sign up for the CMJ Masterpass at https://chrismasterjohnphd.com/masterpass. Use the code LITE10 to get 10% off. To make it easier to get the discount, use this link, which has the coupon already activated: https://masterpass.chrismasterjohnphd.com/cmj-masterpass/2200/buy?coup