Sunday, August 9, 2009

Goat's Milk vs. Cow's Milk

by Richard Crews, M.D.

There are two significant nutritional differences between goat's milk and cow's milk: (1) goat's milk tends to be less allergenic than cow's milk (discussed below), and (2) goat's milk is less generative of atherosclerosis (hardening of the arteries, high blood pressure) than cow's milk (also discussed below).

There are two false problems that worry some people: (3) goat's milk tends to be more expensive commercially than cow's milk (discussed below), and (4) goat's milk may have a bad taste compared with cow's milk (also discussed below).

In general, milk from goats is very similar to milk from cows. Culturally, goat's milk is used more widely around the world than cow's milk; and historically, goat's milk has been used many centuries longer and in more widely diverse environmental settings than cow's milk.

The high protein content and excellent nutritional value of goat's milk is closely comparable to cow's milk. They have similar caloric loads (which means the number of calories that must be ingested to get comparable protein, vitamin, and mineral nutritional value). Unfortunately, they also both have the milk-sugar "lactose" to which some people are intolerant (and get digestive upsets from).

(1) As to how and why goat's milk tends to be hypoallergenic (it almost never causes allergic reactions), there has been considerable scientific exploration and speculation about this phenomenon, but the final answer is not entirely understood. Apparently it is because the proteins of the two kinds of milk are different and the protein fragments of goat's milk after digestion seem to trigger human allergic reactions much less frequently than cow's milk. In a cultural setting where drinking cow's milk is the norm, goat's milk can provide a valuable, nutritionally equivalent alternative for people who develop an allergic reaction to cow's milk.

(2) With regard to goat's milk being less conducive than cow's milk to the absorption of cholesterol (which causes hardening of the arteries and high blood pressure), this has been well established. It is because the fats of goat's milk are significantly different from those of cow's milk. Basic biological fats are called "triglycerides"; they consist of long-chain carbon compounds (chemically, in the form of "fatty acids") attached to the three hydroxyl groups of glycerol (or "glycerin"). But with cow's milk, these tend to be longer carbon chains, especially myristic acid (14 carbons long), palmitic acid (16 carbons long) and stearic acid (18 carbons long). The dominant fatty acids of goat's milk are caproic acid (6 carbons long), capryllic acid (8 carbons long), and capric acid (10 carbons long). (It is interesting to notice that the three words "caproic," "capryllic," and "capric" are all derived from the Latin word "caper" meaning "goat.") Longer fatty acids facilitate the absorption and metabolic integration of cholesterol more than shorter fatty acids do. Cow's milk therefore contributes significantly more than goat's milk to the formation of cholesterol-based atherosclerotic plaques in arteries and, therefore, to high blood pressure.

The shorter fatty acids of goat's milk have another interesting effect: they make the fats of goat's milk mix more easily with the water phase of the milk. This is why goat's milk tends to be naturally "homogenized" and not require special processing to keep the fats (that is, the cream) from separating.

(3) The reason goat's milk tends to be more expensive than cow's milk is that commercial production of cow's milk is routinely done in a factory-like way with cows held by the hundreds in tiny stalls, unable to move about, standing throughout their lives in their own manure, fed grains and cheap bulk foods at one end and drained of milk at the other end. Goats simply will not tolerate this kind of inhumane treatment--they rebel, they have aberrant behavioral outbursts, and they die. They are more intelligent and emotionally sensitive than cows and cannot be "factory-ized." Hence they are more expensive to tend, to feed, and to milk.

In recent years as factory-like handling of cow-milk production has become the commercial norm, the term "organic" has come to apply to cows that are treated humanely--they are allowed to range around a bit, to graze, and generally to live more normal cow-like lives. They are also not loaded with antibiotics to counteract the infections that run rampant in crowded, manure-contaminated cage quarters; such infections do not occur much in a freer range environment, and when they do, they are handled by the animal's normal immune system. Furthermore, the milk production of "organic" cows is not boosted artificially by hormone injections as is done routinely with factory-handled cows. Both antibiotics and hormones can be carried through as contaminants in non-organic cow's milk.

(4) As to the reputation that goat's milk has that is tastes bad, this is due to two factors. First, although goats are fastidious and picky in what they are willing to eat, their digestive systems are more hardy and versitile than cows; goats can digest a wide variety of food sources, both fresh and foul. If goats are hungry, they can and will eat garbage, and the bad tastes and smells of the garbage they eat can be carried through to the milk they produce. Second, male goats (called "billies") emit a pungent, musty, goaty smell. If the males and females are allowed to hang around together (other than for a week or two once or twice a year so they can mate), the pungent, musty, goaty smell is carried through to the milk. To prevent this, billy goats are commonly kept in separate pastures and allowed access to the females only for mating purposes.

In summary, goat's milk is a healthy, delicious, hypoallergenic, non-atherosclerosis producing alternative to cow's milk. It is commonly more expensive than cow's milk because of the streamlined but inhumane, factory-style production methods to which cows are subjected, but since it has significant nutritional advantages to cow's milk, perhaps this is a price premium we should be willing to pay.