Vitamin B1 basics
Feeling sluggish? You could blame the weather. Or stress. But maybe all you need is a boost in your vitamin B1 levels.
Why B1 is important
Known as thiamine (the "energy nutrient"), vitamin B1 is responsible for many cellular interactions in the body. The most important may be aerobic energy production -- in which your cells use oxygen to convert carbohydrates and other sugars into energy. Without adequate levels of vitamin B1, this process would slow or stop altogether.This important nutrient also plays a key role in supporting the nervous system and protecting your nerves from degeneration and damage. Vitamin B1 helps your organs and nerves relay messages to one another, such as when your brain tells your leg muscle to twitch.
Signs and symptoms of a vitamin B1 deficiency
Vitamin B1 deficiencies (commonly called "beriberi") are rare, but that doesn't mean you shouldn't worry. Signs and symptoms to look for include:
- Loss of appetite
- Tiredness or extreme feelings of laziness
- Indigestion or constipation
- Muscle tenderness, particularly in the calf muscles
- "Pins and needles" sensations or numbness in the arms and legs
Though it is never recommended to megadose on any vitamins or minerals, there is little to no risk of overdosing on vitamin B1. Even in the most extreme cases (through intravenous means or taken as a supplement), toxicity symptoms are rare.
Who is at risk for B1 deficiency?
Certain dietary and health conditions can affect how vitamin B1 interacts with the body's cells. As a result, several groups are at high risk of running low on the nutrient:
- Alcoholics. The leading cause of vitamin B1 deficiency across North America is alcoholism. People who drink to excess often have a harder time absorbing and retaining it (vitamin B1 is easily excreted in the urine). Depending on the levels of alcohol-induced damage to the liver or kidneys, alcoholics may need 10 to 100 times more vitamin B1 than people who don't drink.
- Coffee or tea drinkers. If you drink more than three cups of coffee a day, you may need five to 10 times the amount of vitamin B1 than other people. That's largely because you'll excrete more of the nutrient through your kidneys and into your urine.
- People who suffer from chronic health conditions. Researchers believe some chronic health conditions (for example, diarrhea and stress) inhibit the body's ability to absorb vitamin B1. If you are suffering from a chronic health problem, talk to your doctor about supplementation.
Recommended daily intake for vitamin B1
The Recommended Dietary Allowance (RDA) for vitamin B1 is:
- Infants (0 to 6 months): 200 micrograms (mcg) per day
- Infants (7 to 11 months): 300 mcg per day
- Children (ages 1 to 3): 500 mcg per day
- Children (ages 4 to 8): 600 mg per day
- Children (ages 9 to 13): 900 mcg per day
- Males (ages 14 and older): 1.2 milligrams (mg) per day
- Females (ages 14 and older): 1.1 mg per day
- Pregnant women: 1.4 mg per day
- Lactating women: 1.5 mg per day
Good food sources of vitamin B1
If you eat a healthy, balanced diet, getting enough vitamin B1 should be no problem. Some of the best sources include:
- Sunflower seeds, raw, 1/4 cup = 0.82 mg
- Tuna, yellowfin, baked/broiled, 4 ounces = 0.57 mg
- Black beans, cooked, 1 cup = 0.42 mg
- Lentils, cooked, 1 cup = 0.33 mg
- Asparagus, boiled, 1 cup = 0.22 mg
- Romaine lettuce, 2 cups = 0.11 mg
Tips for getting more vitamin B1 in your diet
- Limit alcohol and coffee. Caffeinated beverages increase your body's need to urinate. The more you urinate, the more vitamin B1 your body excretes.
- Be mindful about cooking certain foods. Vitamin B1 is extremely sensitive to heat, so overcooking your foods could cut their vitamin B1 content in half. (This is especially true of green beans.)
- Eat unprocessed foods. Like most other nutrients, 20 to 60 percent of the vitamin B1 content in wheat is lost when it's processed. Processed foods tend to be less nutritious all the way around than fresh, wholesome foods.
- Store your food properly. Because vitamin B1 is sensitive to temperature changes, storing food in your fridge for too long can cut its nutrient content. Try buying fresh foods as you need them instead of buying them in bulk.