❤️ Colostrum

Colostrum is the first milk, which appears at the end of pregnancy and in the first days after birth. EU law defines it as the fluid secreted by the mammary glands for three to five days after giving birth, rich in antibodies and minerals. It is thick and golden yellow. Cow colostrum contains 14–16 g of protein per 100 g versus 3.1–3.2 g in ordinary milk, and about 50 g of immunoglobulin G per litre versus less than 1 g.

WHO calls colostrum the perfect first food for a newborn and advises putting the baby to the breast within the first hour after birth. There isn't much colostrum: the NHS says a baby needs only about a teaspoon per feed, because it is very concentrated. Around day 2–4 the breasts fill up and there is more milk. In the first days a baby is fed often, every 1–3 hours.

For calves colostrum matters even more: almost no maternal antibodies reach them through the placenta. Utah State University recommends giving a calf colostrum equal to 10–12% of its body weight, that is 3–4 L, within the first 1–2 hours; after 12 hours antibody absorption drops sharply, and after about a day the gut no longer lets them through. Quality is checked with a refractometer: a Brix reading of 22% or more means at least 50 g of immunoglobulins per litre.

Colostrum or breast milk? Colostrum is the first milk of the first three to five days, thick and golden yellow, and there is not much of it; around day 2–4 the breasts fill up and there is more milk. Colostrum or ordinary cow's milk? Cow colostrum has 14–16 g of protein per 100 g against 3.1–3.2 g in ordinary milk, and about 50 g of immunoglobulin G per litre against less than 1 g. Colostrum or a supplement? The powders sold as bovine colostrum are a different thing from the newborn's first feed, and EFSA found no evidence for their claimed effects.

Human colostrum is never sold. On shelves you will meet only supplements labelled “bovine colostrum”, as capsules or powder, mostly in pharmacies, health-food shops and sports nutrition shops. Read any promise of “immunity” or sport benefits with caution, since EFSA's 2011 opinion found no established cause-and-effect relationship. For calves on a farm, colostrum quality is checked with a refractometer: a Brix reading of 22% or more means at least 50 g of immunoglobulins per litre.

Why it matters to you. Colostrum should not be expressed and thrown away: in many countries this is still done, and WHO warns that it deprives the baby of protection. Bovine colostrum supplements are sold “for immunity” and for sport, but in 2011 EFSA found no evidence of such effects: a cause-and-effect relationship was not established.