Vitamin
Vitamin B1 (Thiamine)
Turns carbohydrate into energy and supports nerve signalling. Because the body stores very little, a steady daily intake matters.
Women: 1.1 mg/dayMen: 1.2 mg/day
Best food sources
Fruit
- Oranges (small amounts)
- Watermelon (small amounts)
Vegetables
- Green peas
- Asparagus
- Acorn squash
- Brussels sprouts
Other plant foods
- Sunflower seeds
- Flaxseed
- Black beans
- Lentils
- Oats
- Brown rice
- Whole wheat
- Nutritional yeast
Animal foods
- Pork loin
- Trout
- Salmon
- Mussels
How much is in a serving
- 1 oz sunflower seeds: about 0.4 mg
- 1 cup cooked black beans: about 0.4 mg
- 1 cup cooked lentils: about 0.3 mg
- 3 oz pork loin: about 0.8 mg
Deficiency signs
Fatigue, irritability and poor concentration early on; severe deficiency causes beriberi, which affects nerves and the heart. Highest risk with heavy alcohol use, bariatric surgery or diets built on white rice and refined flour.
These signs overlap with many other conditions. A blood test through your doctor is the only way to confirm a deficiency; do not start high-dose supplements on a guess.
Absorption and interactions
- Alcohol reduces absorption and increases loss.
- Raw fish and some teas contain compounds that break thiamine down.
- Lost into cooking water; steam or use the liquid.
Meal ideas
- Black bean and brown rice bowl
- Sunflower seed and oat granola
- Lentil soup with peas
- Pork loin with roasted squash
Planner meals richest in Vitamin B1
Per serving, from the meal planner’s library. Percentages use the average adult reference intake.
- Barley risotto with mushrooms and peas1.2 mg · 106%
- Pork loin with roasted squash and greens1.2 mg · 102%
- Turmeric tofu scramble with spinach1.1 mg · 98%
- Lentil bolognese with whole wheat pasta1.1 mg · 96%
- Tofu and mushroom scramble with greens0.8 mg · 70%
- Butternut squash and white bean pasta0.8 mg · 70%