Top 7 foods rich in vitamin B1

Vitamin B1: definition, benefits & recommended intakes

What is vitamin B1?

Vitamin B1, also known as thiamine, is a water-soluble vitamin.

Present only in food (the body does not manufacture it), it is absorbed in the duodenum and small intestine, then activated by the liver before circulating in the body in two active forms that are essential for proper cell function:

• TDP (thiamine diphosphate), which is involved in the production of energy from carbohydrates
• TTP (thiamine triphosphate), which plays a role in the transmission of nerve impulses

It was while studying beriberi, a disease linked to a diet very low in nutrients, that researchers in the early 20th century discovered vitamin B1.

They realised that rice bran, rich in B1, protected against this syndrome: a major breakthrough that made B1 the first vitamin to be isolated.

The benefits of vitamin B1

Vitamin B1, or thiamine, plays an essential role in the body.

It acts as an enzyme cofactor in key reactions that enable nutrients to be converted into energy that can be used by the cells.

It therefore contributes to a number of vital mechanisms, including:

• energy metabolism: in its active forms (TDP and TTP), thiamine helps to produce ATP, the main source of cellular energy;
• the nervous system and psychological functions: it promotes glucose metabolism in the brain, contributing to memory, concentration and the transmission of nerve impulses;
• heart health: it plays a part in the normal functioning of the heart, which is a major consumer of ATP.

What is the recommended daily intake of vitamin B1?

According to the World Health Organisation (WHO), the recommended daily requirement is 1.1 mg for adult women and 1.2 mg for men.

A deficiency in vitamin B1 can lead to fatigue, weight loss and nervous and cardiac problems; therefore, it is very important to monitor your intake carefully.

Where can I find vitamin B1 in food?

A vitamin that is not stored

The body does not store vitamin B1, so you need to consume it regularly (1).

However, beware of the high heat of cooking, which degrades it.

7 foods rich in vitamin B1

Here are the top 7 foods that are particularly rich in vitamin B1 (with average levels indicated per 100g), from the least rich source to the richest:

1. Pork (fillet, ham): 0.8 to 1.2 mg

Among animal products, pork is one of the best sources of thiamine.

It is found in particular in tenderloin, roast pork, cutlets and cooked ham (approximately 0.6 to 0.8 mg of B1 per 100 g).

Easy to incorporate into everyday meals, pork provides a good source, provided it is cooked gently (steamed or at low temperature), as thiamine is sensitive to prolonged heat.

2. Pine nuts: 0.9 to 1.0 mg

Pine nuts are seeds often used in salads or pestos, which provide a good quantity of B1.

They should be eaten raw or just dry toasted to preserve their nutritional richness.

3. Macadamia nuts: 1.2 to 1.3 mg

Delicious and crunchy, macadamias are an excellent plant source of vitamin B1.

To get the most out of them, eat them plain or lightly roasted without adding any fat.

4. Sunflower seeds: 1.5 to 2.0 mg

Easy to sprinkle in yoghurt, salads or bread dough, sunflower seeds are a readily available plant source of thiamine.

Here again, it's best to avoid roasting them at high temperatures.

5. Wheat germ: 1.5 to 2.0 mg

Highly concentrated in micronutrients and with a light nutty flavour, wheat germ is easy to add to smoothies, compotes or mueslis.

Once again, it's best eaten raw, as heat destroys much of its vitamin content.

6. Rice bran: 2.0 to 4.0 mg

Little known, rice bran is actually the outer layer of the grain, where vitamin B1 is concentrated.

It can be added in small quantities to foods, provided it is not processed or heated.

7. Brewer's yeast (dry): 10 to 15 mg

Brewer's yeast is the champion source across all categories.

Very rich in thiamine (and other B vitamins), it generally comes in the form of flakes or powder, to be sprinkled on cold or warm dishes.

Avoid cooking it to retain all its benefits.

Foods richest in B1 in absolute terms

The ranking above highlights foods rich in vitamin B1 that are easy to consume on a daily basis, although in absolute terms the highest levels are found in: dried brewer's yeast, rice bran with the fat removed, sunflower seeds, wheat germ, poppy seeds, macadamia nuts and linseed.

Which fruit contains vitamin B1?

Although fruit is not the most concentrated source of natural vitamin B1, some fruits contain amounts that are useful for supplementing your daily intake.

For example, oranges, mangoes, watermelons and bananas contain small doses.

You can easily add them to a snack or breakfast.

On average, a banana provides around 0.04 to 0.05 mg of vitamin B1, which is modest but not negligible if eaten regularly as part of a varied diet.

Another advantage of fruit is that it's raw, so there's no loss from cooking, which is often damaging to this heat- and water-sensitive vitamin.

In other words, fruit can supplement your B1 intake, but should not be your main source.

What influences the absorption of vitamin B1?

Thiamine absorption depends on several factors.

It relies on specific active transporters (ThTR 1, ThTR 2), the effectiveness of which can be impaired by certain drugs (such as antacids), genetic mutations, symptoms like digestive disorders, or the consumption of alcohol.

Some substances and foods also influence the absorption of vitamin B1: raw cabbage, tea, shellfish and bacteria present in certain raw fish.

The rate of absorption of B1 varies according to the quantity ingested: it is very high (almost 100%) at normal doses, but decreases when large quantities are consumed (2).

Finally, magnesium is important because it helps to activate thiamine in the TDP form.

A magnesium deficiency can therefore limit the effectiveness of vitamin B.

The best food supplements for boosting your B1 levels

Discover benfotiamine: highly assimilable

Food supplements can help you to increase your intake of vitamin B1, for example, in cases of deficiency or absorption problems.

Benfotiamine in particular, a fat-soluble form of B1, is characterised by its high bioavailability (3): it is better absorbed and remains active in the body for longer.

Find out more about the highly bioavailable fat-soluble form of Benfotiamine.

Vitamin B complexes

Note also that a good overall intake of B group vitamins (such as B2, B3, B6, B9 or B12) supports the metabolic processes in which vitamin B1 is involved (4).

Discover Coenzymated B Vitamins, a complex in which B1 is combined with other active B vitamins.

The convenience of multivitamins

For overall support, quality multivitamins are a good option.

They can provide you with all the B vitamins, as well as the magnesium essential for the effectiveness of thiamine.

Discover Daily 2® Timed Release, Daily 3® and Daily 6® multivitamin supplements, which help you meet your various daily micronutrient needs in a convenient format.