Is Milk Bad for Acne?Finally medical researchers have affirmed that diary products do worsen acne. How does milk affect acne and what are the precautions to be taken?
As early as 1949, Robinson had published a study in the South Medical Journal that stated that the majority of the1925 acne patients in his study that kept a food diary reported that milk was the commonest food that was associated with their acne flare ups.
His study was relegated to the background when two studies by Fulton et al (1969) and Anderson (1971) failed to find any association between acne and chocolates, milk, roasted peanuts and cola. Both these studies were later discredited because of the small number of subjects, a shorter duration of follow up and inadequate choice of controls chosen for comparison.
More recently, Adebamowo and his colleagues from the Harvard University found positive relationship between milk consumption and acne eruptions in a survey conducted among 47,335 nurses. Their study was interesting as it revealed a stronger association with skim milk than whole milk, indicating that the fat content of milk may not be the reason for acne flare ups. Similar observations were made among high school teenagers in other studies as well.
How Does Milk Affect Acne?
The reason for the negative effects of milk products on acne is thought to be due to the presence of hormones and biologically active substances in the diary products. Most of the consumable milk is produced from pregnant cows; the main reason for high levels of hormones in milk. Hormonal levels are also high in just delivered cows and cows treated with bovine growth hormones.
Allergy to milk protein resulting in an inflammatory reaction and blockage of the hair follicle and sebaceous glands has also been cited as a contributing factor for worsening of acne following consumption of milk.
Iodine fortified food is given to the cows to fight infection and iodine solutions are liberally used to cleanse the udders and milking equipments in the diary farms. This may result in higher than normal levels of iodine content in the milk and other milk products. For acne sufferers this is bad news, as iodine, iodides and other halides have been shown to worsen acne eruptions in a number of studies.
It is now clear that milk contains a number of substances which act as acne triggers.
Hormones in Milk Responsible for Acne Flare Ups
Milk, especially those from pregnant cows and just-delivered cows, contains high levels of hormones like progesterone and precursors of di-hydro-testosterone. Increased levels of these hormones increase the sebaceous gland activity and the oily sebum output, resulting in aggravation of acne in teens.
Other hormones present in milk are also implicated as culprits in worsening of acne. The most frequently involved hormone is the IGF-1(insulin-like growth factor). This is present in organic milk and milk from cows treated with bovine growth hormone. IGF-1 levels are increased in the body in response to increased secretion of insulin. IGF-1 has a stimulatory effect on the sebum production in the sebaceous glands, one of the main events in the development of acne.
The effect of IGF-1 in response to increased insulin levels in the blood is also thought to be the cause of high incidence of acne following consumption of refined carbohydrates, the so-called high glycemic index foods. The same mechanism is responsible for the increased prevalence of acne among women suffering from the polycystic ovarian syndrome.
It will be interesting if a few studies are undertaken to see whether milk derived from home grown cows fed on natural feeds and grass has any adverse effects on the natural course of acne.
As the food-acne relationship is no more a myth, acne affected teenagers would do well to avoid excessive intake of diary products and other food items that affect acne.