Kefir is a fermented drink produced from milk and kefir grains -- small, gelatinous bundles of curdled casein that resemble cauliflower florets. These grains contain lactic acid bacteria, acetic acid bacteria and yeast. The drink has existed for thousands of years, originating in the Caucasus Mountains in Eurasia. Kefir can vary in taste and composition based on the type of milk used, with cow, goat, rice, soy, sheep and coconut milk all possibilities. Cow’s milk, however, is most commonly used.
Nutrition of Kefir
Kefir is full of vitamins, minerals and essential amino acids. The amounts of each component varies based on the type of milk, the kefir grains and the fermentation process used. Kefir contains around 12 milligrams of magnesium per 100 grams, or about 3.5 fluid ounces of the drink. It is also a good source of vitamins B-1 and B-12, biotin, calcium, folic acid, vitamin K and phosphorus. There is a smaller amount of lactose in kefir compared to regular milk, which may be beneficial for individuals with lactose intolerance.
Functions of Magnesium
Kefir is rich in magnesium, which is an important part of neuromuscular transmission; it acts as a muscle relaxer in the contraction-relaxation process. Magnesium is required in the processes of fatty acid and protein synthesis. It is also involved in the glycolytic pathway, the metabolic pathway for glucose. One of magnesium’s major functions is the stabilization of the adenosine triphosphate, or ATP, molecular structure, which plays an important role in many metabolic pathways in the body.
Magnesium and Calcium
Magnesium is one of the three nutrients important for bone health; calcium and vitamin D complete the trio. Though calcium is the major mineral responsible for bone structure and strength, the body cannot absorb it without magnesium. The presence of adequate amounts of magnesium helps suppress parathyroid hormone, which serves to remove calcium from bone, possibly leading to osteoporosis if unchecked. Kefir contains both calcium and magnesium, and thus may help improve bone health.
Other Health Benefits of Kefir
Kefir's antimicrobial activity improves gut health, controls serum glucose, cholesterol and lactose intolerance, supports the immune system and controls several types of cellular cancer. The February 14, 2011 issue of "Cancer Management and Research," published the results of a study that tested the effect of kefir on adult lymphoblastic leukemia, which affects children as well as adults. Kefir demonstrated the ability to reduce the spread of malignant cells and precipitate their death without any harm to normal cells. Further evaluation of kefir is recommended.
- Cancer Management and Research: Kefir Induces Cell-Cycle Arrest and Apoptosis in HTLV-1-Negative Malignant T-Lymphocytes
- Probiotic.org: Kefir
- Krause’s Food, Nutrition, and Diet Therapy; L. Kathleen Mahan et al.
- Critical Reviews in Food Science and Nutrition: Kefir and Health: A Contemporary Perspective