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  4. Thiamine Benefits: What Makes it Essential for Energy & Focus

Thiamine Benefits: What Makes it Essential for Energy & Focus

Thiamine supports energy production and the nervous system. Find out why that’s so important—and where to find vitamin B1.

3 MIN READ — 03/20/2025

Do you often feel tired, have no appetite, and struggle to concentrate? This might be related to thiamine. Vitamin B1 supports many essential functions in your body, such as energy metabolism and the nervous system. Learn more about this essential B-vitamin here.

Table of Contents

  • 01.

    What Exactly is Thiamine?

  • 02.

    Why is Vitamin B1 So Important?

  • 03.

    What’s the Recommended Daily Intake of Thiamine?

  • 04.

    Which Foods Contain Vitamin B1?

  • 05.

    How Can I Recognise a Thiamine Deficiency?

At a Glance

  • 01.

    Thiamine, also known as vitamin B1, is a vital nutrient that supports energy metabolism and the nervous system.

  • 02.

    Since our bodies can’t produce vitamin B1, we need to get it through our diet. A varied, balanced diet helps meet the recommended daily intake, and supplements are also available.

  • 03.

    Vitamin B1 is sensitive to heat, oxygen, UV light, and being stored in water. So, be sure to eat thiamine-rich foods raw or gently cooked.

What Exactly is Thiamine?

Thiamine is the official name for vitamin B1. It was the first of the eight B-vitamins to be discovered, and because of its important role in supporting nerve cells, the nervous system, and energy metabolism, thiamine is considered a vital nutrient. It’s often referred to as the "nerve vitamin" or "energy vitamin" for this reason.

Our bodies can’t produce vitamin B1 on their own, so we need to get it through food. And since we can’t store this water-soluble vitamin either, it’s important to include thiamine-rich foods in your daily diet.

Fun fact: The discovery was made in the early 20th century by Polish biochemist Casimir Funk, who found that removing the outer layers of rice grains led to nutrient deficiencies and Beriberi (a disease that occurs in people lacking thiamine).

Why is Vitamin B1 So Important?

Vitamin B1 is essential for our bodies as it helps break down proteins and carbohydrates so they can be used for energy. Along with proteins and the trace element manganese, thiamine helps form enzymes in the liver that convert carbohydrates into glucose (sugar), which fuels our energy metabolism.

But that’s not all it does. While most cells in the body can use fats and proteins for energy, nerve and brain cells rely solely on glucose—and therefore on vitamin B1—to perform their functions. Thiamine helps convert glucose into energy, ensuring the flow of information between nerves and throughout the nervous system.

And what else is vitamin B1 good for? The brain also uses glucose to produce serotonin, the so-called "happy hormone." So, maintaining enough vitamin B1 can help support your focus, energy levels, and mental well-being.

What’s the Recommended Daily Intake of Thiamine?

The German Nutrition Society (DGE), along with the nutrition societies of Switzerland, Austria, and the European Food Safety Authority (EFSA), regularly updates reference values for nutrient intake. The recommended daily intake of vitamin B1 depends on age and lifestyle. Here’s a breakdown in milligrams per day:

  • Infants: 0.2 to 0.3
  • Children (up to 13 years old): 0.6 to 0.9
  • Adolescents and teens (up to 19 years old): 1.0 to 1.4
  • Women: 1.0
  • Men (up to 65 years): 1.2 to 1.3
  • Men (65+ years): 1.1

Pregnant and breastfeeding women are recommended to consume slightly more, around 1.2 to 1.3 mg daily.

Which Foods Contain Vitamin B1?

Thiamine is found primarily in plant-based foods, but it’s also present in beef, pork, fish, milk, and eggs. To ensure you’re getting enough vitamin B1, try incorporating the following foods into your diet:

  • Whole wheat and rye
  • Oats
  • Unpolished rice
  • Flours made from oats, wheat, maize, barley, and rye
  • Legumes like peas and beans
  • Potatoes
  • Asparagus
  • Cauliflower and kale
  • Fennel
  • Lamb’s lettuce
  • Carrots
  • Tomatoes
  • Peanuts, walnuts, Brazil nuts, and almonds
  • Sunflower and cashew seeds
  • Lean beef and pork
  • Offal
  • Fish and shellfish
  • Eggs
  • Dairy products

Thiamine is a delicate vitamin and can be lost through heating, washing, or cooking food in water. Storing foods in open air also reduces thiamine content. To retain as much of the vitamin as possible, try to eat these foods raw or prepare them gently.

In addition to a varied, balanced diet, supplements can help ensure you meet your daily thiamine requirements.

These foods contain thiamine.

These foods contain thiamine.

How Can I Recognise a Thiamine Deficiency?

Signs of a thiamine deficiency include:

  • Fatigue and sluggishness
  • Difficulty concentrating
  • Forgetfulness and confusion
  • Loss of appetite
  • Muscle cramps
  • Increased susceptibility to infections due to a weakened immune system

If these symptoms occur frequently, it’s a good idea to discuss them with your doctor.

Overdosing on vitamin B1 is rare with a balanced diet. In the event of an excess, your body will simply excrete it in your urine.

Article Sources

Deutsche Gesellschaft für Ernährung e. V. (DGE): Was ist Thiamin?
https://www.dge.de/gesunde-ernaehrung/faq/thiamin/

Bundeszentrum für Ernährung (BZfE): Vitamin B1, 2020
https://www.bzfe.de/service/news/aktuelle-meldungen/news-archiv/meldungen-2020/september/vitamin-b1/#:~:text=Vitamin%20B1%20(Thiamin)%20ist%20wasserl%C3%B6slich,den%20Kohlenhydrat%2D%20und%20Aminos%C3%A4urestoffwechsel%20steuern.

European Food Safety Authority (efsa): Scientific Opinion on the substantiation of health claims related to thiamin and reduction of tiredness and fatigue (ID 23) and contribution to normal psychological functions (ID 205) pursuant to Article 13 (1) of Regulation (EC) No 1924/2006, 2010
https://efsa.onlinelibrary.wiley.com/doi/10.2903/j.efsa.2010.1755

Julianna L. Martel, Connor C. Kerndt, Harshit Doshi, Reddog E. Sina, David S. Franklin: Vitamin B1
https://www.ncbi.nlm.nih.gov/books/NBK482360/

Malgorzata Mrowicka, Jerzy Mmrowicki, Grezegorz Dragan, Ireneusz Majsterek: The importance of thiamine (vitamin B1) in humans, 2023
https://pubmed.ncbi.nlm.nih.gov/37389565/

National Institutes of Health: Thiamin – Fact Sheet für Health Professionals, 2023
https://ods.od.nih.gov/factsheets/Thiamin-HealthProfessional/

Derrick Lonsdale: Chapter One – Thiamin, in: Advances in Food and Nutrition Research, 2018
https://www.sciencedirect.com/science/article/abs/pii/S1043452617300372

Öffentliches Gesundheitsportal Österreichs: Vitamin B1, 2024
https://www.gesundheit.gv.at/leben/ernaehrung/vitamine-mineralstoffe/wasserloesliche-vitamine/vitamin-b1.html#:~:text=Vitamin%20B1%20(auch%3A%20Thiamin),zudem%20wichtig%20f%C3%BCr%20das%20Nervensystem.

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Food supplements are not a substitute for a balanced and varied diet and a healthy lifestyle. Do not exceed the indicated daily intake. Keep out of reach of children. Please inform and consult your doctor before consuming this product. Not suitable for children and adolescents under 18 years, pregnant or breastfeeding women. Refrain from taking other food supplements containing zinc. Persons taking anticoagulant medication should seek medical advice before consuming vitamin K-containing supplements.

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↡ Ongoing survey of 3,000+ AG1 customers after 12+ days of use, 2024.

§ In a third-party, observational study conducted on 35 healthy adults ages 25-48 assessing the self-perceived efficacy of AG1 over the course of 3 months. The study was conducted on a similar version of AG1's continually evolving formulation. The study results are transferable because of comparable ingredients and amounts.

○ Ongoing survey of customers from 12 European countries who have been taking AG1 for an average of 9 days.

⬥ AG1 single subscriptions price and dose-matched average aggregated prices in 9 individual nutritional supplement categories with comparable ingredients. The prices of the individual supplements are the average prices of three individual products available online for each compared category, each with comparable ingredients. To ensure a fair basis for comparison, where the comparison products have different dosages, the prices were mathematically adjusted to correspond to the dosage contained in AG1. The 9 compared categories are vitamin B12, folate (Methylfolate), vitamin C, vitamin E, bacterial cultures, zinc, coenzyme Q10, greens powder and fibre.

Research Studies
a. In a triple-blind, randomised, placebo-controlled parallel-designed clinical trial evaluating nutrient biomarkers and microbiome shifts in 105 healthy adults ages 20-59 over the course of 12 weeks.
b. In a double-blind, randomised, placebo-controlled 2-week cross-over clinical trial assessing microbiome shifts in 20 active adults ages 19-37.
c. In a double-blind, randomised, placebo-controlled 2-week cross-over clinical trial assessing microbiome shifts of 24 healthy adults with occasional GI distress ages 26-59.
d. In a double-blind, randomised, placebo-controlled cross-over clinical trial assessing bioavailability in 16 healthy adults ages 18-42 over the course of 8 hours.
The studies were conducted on a similar version of AG1's continually evolving formulation. The transferability of the study results is ensured because of comparable ingredients and amounts.

◊ Key health benefits:

(1) Immune system: With vitamins A, C, B6 and B12 as well as folate, zinc, copper and selenium, AG1 contributes to the normal function of the immune system. Vitamin C contributes to maintain the normal function of the immune system during and after intense physical exercise. 200 mg Vitamin C taken daily in addition to the recommended daily dose (80 mg) contributes to the normal function of the immune system during and after intensive physical activity.

(2) Energy levels: Vitamins C, B6, B12, riboflavin, niacin, pantothenic acid and magnesium contribute to normal energy-yielding metabolism and to the reduction of tiredness and fatigue. Magnesium contributes to electrolyte balance. Biotin, zinc and chromium contribute to normal macronutrient metabolism.

(3) Digestion: Calcium contributes to the normal function of digestive enzymes. With vitamin A, biotin, riboflavin and niacin, AG1 contributes to the maintenance of normal mucous membranes (e.g. intestinal mucosa).

(4) Focus; Mental performance; Psychological function; Nervous system: With pantothenic acid, AG1 contributes to normal mental performance. Zinc contributes to normal cognitive function. With vitamins C, B6, B12, B1, B3 and B7 AG1 contributes to normal psychological function and to normal functioning of the nervous system. Calcium contributes to normal neurotransmission.

‡ Additional health benefits:

(5) Muscles: With calcium and magnesium, AG1 contributes to normal muscle function.

(6) Cell Protection: With vitamins E and C as well as riboflavin, zinc, copper and selenium, AG1 contributes to the protection of cells from oxidative stress. Phosphorus contributes to normal function of cell membranes. Folate, Vitamin B6 and B12 contribute to normal homocysteine metabolism.

(7) Skin, hair & nails: With vitamins A, as well as riboflavin, niacin, biotin and zinc, AG1 contributes to the maintenance of normal skin. Vitamin C contributes to normal collagen formation for the normal function of skin. Copper contributes to normal connective tissue. Vitamin B7, zinc and selenium contribute to the maintenance of normal hair. Zinc and selenium contribute to the maintenance of normal nails.

(8) Hormonal system: With vitamin B6, AG1 contributes to the regulation of hormonal activity. Zinc contributes to the maintenance of normal testosterone levels in the blood. Selenium contributes to the normal thyroid function. With chromium, AG1 contributes to the maintenance of normal blood glucose levels.

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