Winter milk contains more calcium
European dairy cows produce milk with higher levels of calcium in
the winter months of the year than they do in the summer months.
The study was carried out by Professor Jindra Lukasova and a colleague at the University of Veterinary and Pharmaceutical Science in Brno. The results build on research that was carried out in 1973 that found a connection between the winter fodder feed to cows, and the increase of calcium content in cows milk.
Researchers concluded that a number of factors can effect the calcium mineral and vitamin levels in a cow's milk production. These include the animal's physical condition, genetic characteristics, food, health and the way the cow is cared for.
200 dairy cows were tested in the study and the tests were carried out before and after pasteurization. The study found that calcium content for cows in the lowlands of the Czech Republic was 1.11 grams of calcium per litre in the summer and 1.22 grams of calcium per litre in the winter.
Cows that grazed in the mountains, and higher altitudes overall had elevated calcium levels in their milk. In the summer these cows had an average of 1.28 grams of calcium in the summer and 1.37 in the winter.
Dairy foods are the primary source of calcium for Europeans. The daily recommended intake of calcium for teenagers is 1.3 grams - the equivalent of four servings of milk, cheese or yogurt daily and for adults the daily intake of milk is 1.0 grams per day which amounts to three or four small glasses of milk.
