Vitamin B1 (thiamine)
A water-soluble vitamin essential for carbohydrate energy metabolism and a properly functioning nervous system, whose historic deficiency caused beriberi.
Vitamin B1 (thiamine) is a key cofactor in the metabolism of carbohydrates: it allows glucose to be turned into energy (via the Krebs cycle). The nervous system and the heart, which use a lot of energy, depend heavily on it.
The original angle (the paradox of white rice and sugar): B1 illustrates a nutritional trap that is both historic and current. It is concentrated in the outer layers of cereal grains, which refining removes. The switch from brown rice to white rice in the 19th century (in Asia) triggered epidemics of beriberi (nerve and heart damage), the first deficiency disease to be identified as such.
A current paradox: the more refined carbohydrates and sugar you eat, the more B1 you need to metabolise them… yet these refined foods are precisely devoid of it. A diet rich in sugar and white flour can therefore « drain » your B1 reserves while supplying none, a little-known vicious circle.
Alcohol, the great thief of B1: alcohol strongly disrupts the absorption and storage of thiamine. B1 deficiency is common in people with alcohol dependence, causing serious neurological damage (Wernicke-Korsakoff syndrome). This is why B1 is routinely given during alcohol withdrawal.
Fragility: thiamine is sensitive to heat, to cooking water (it dissolves into it) and to certain compounds (thiaminases in some raw fish, sulphites). Gentle cooking and reusing the cooking water preserve B1.
Sources: wholegrain cereals, pulses, pork, sunflower seeds, yeast, nuts, offal. Since refining is a key factor, choose the wholegrain versions of cereals.