What Foods Are Highest in Vitamin B1 (Thiamine)? 

Why does vitamin B1 matter?

Vitamin B1, also called thiamine, is required for the enzymes that let your cells turn glucose into usable energy. Your nerves and your brain rely very heavily on this. If you're deficient in thiamine, the common symptoms are neuropathy, brain fog and fatigue.

What are the top 7 foods highest in vitamin B1?

These amounts are per 100 gram serving, which is about 3 and a half ounces:

1. Pork chops: about 0.6 milligrams (pork tenderloin is closer to 1 milligram). Pork is the best usable source of vitamin B1 because your body absorbs it better, and one serving can meet most of your daily requirement.
2. Pork liver: a good source of B1, and very dense in all the B vitamins. Some people love it, some people don't.
3. Sunflower seeds: about 1.48 milligrams, but the bioavailability is not nearly as high as pork or pork liver, so your body can't use all of it. I always eat any seed roasted, preferably sprouted and roasted.
4. Macadamia nuts: about 1.19 milligrams. They have anti-nutrients, and if you don't roast them thoroughly you won't have access to much of that B1.
5. Pine nuts: a good source. The same anti-nutrient warning applies.
6. Trout: about 0.43 milligrams. It's far and away the best fish or seafood source of B1.
7. Tuna: about 0.04 milligrams, even cooked. It's inexpensive, and it works on carnivore or keto.

Do you have to eat pork every day?

No. You can store about a 10-day supply of B1, so eating that amount of pork one, two or three days a week keeps your stores up. To be safe, I'd eat it two or three times a week. B1 is a water-soluble vitamin, so unlike the fat-soluble vitamins, your body cannot store a long-term supply.

If you can't eat pork for religious reasons or you just hate it, sunflower seeds, macadamia nuts and pine nuts are the three plant sources. In my opinion, though, you just need to eat some pork two or three times a week.

Is bacon a good source of vitamin B1?

Not really. I love bacon, but when you cure it, smoke it and then cook it with high heat, you lose about 85% of the vitamin B1. If well-done crispy bacon is your only pork, it's not the best way to get B1.

Is beef a good source of vitamin B1?

Beef has all the other B vitamins, but it is not a great source of B1. So to all my carnivore brothers and sisters, especially if you're on the lion diet, include some pork once, twice or three times a week so you can get your B1 without a supplement. I'd much rather you get B1 from food than buy a B1 supplement.

What blocks or destroys vitamin B1?

You can eat a diet full of B1 and still end up deficient if any of these are going on:

• Coffee and tea: they contain tannins. A pot of coffee every day plus a lowish B1 diet can leave you deficient.
• Alcohol: it blocks absorption and makes you pee out B1 before your body can use it.
• Raw fish eaten very often: it contains thiaminase, an enzyme that breaks down B1. Sushi, sashimi or raw oysters now and then is fine. If it's every day, prioritize B1-rich foods.
• Sulfites: in wine, dried fruit, some processed meats and some salad bars. They break down thiamine before your body can use it.
• Some medications: loop diuretics like Lasix, thiazide diuretics like HCTZ, and metformin for diabetes, prediabetes and metabolic syndrome can all leave you effectively B1 deficient.
• Low magnesium: you need enough magnesium to use the B1 you get from food.