Ask a Dietitian

As seen on BCTV

ORGANIC VS CONVENTIONAL MILK

Canada’s Food Guide to Healthy Eating recommends 2-4 servings of milk and milk products per day. The key nutrients we get from milk include protein, carbohydrates, fat, calcium vitamin D, B vitamins and vitamin A (among others).
When choosing which milk to buy it is recommended that you choose lower fat milk after the age of 2 an homogenized milk for 1-2 year olds. If you are trying to gain weight then drinking 2% or homo is acceptable. Be aware though that the higher the milk fat %, the more saturated fat you are consuming.
The other factor people consider when making food choices these days is whether or not they are organic. There are many issues pertaining to milk in terms of what substances are added during the dairy cow’s lifetime, processing of the product and packaging. Growth hormones and antibiotics are of increased public concern, and the issue of non-organic vs. organic milk is continually on the rise.
According to the BC Dairy Foundation, milk is natural – nothing is added after leaving the animal except vitamins A and D, which are required by law. Thus, the concerns about the contents of milk pertain to the source, the dairy cow.

Hormones (or lack thereof) in milk

Hormones in milk are of great public concern, especially rBGH (Recombinant Bovine Growth Hormone), the genetically engineered form of the hormone BST (Bovine Somatotropin). However, growth hormones such as BST and rBGH are not legal for use within Canada with dairy cows, thus, are not really an issue in terms of milk consumption within Canada.
rBGH has varying effects on both dairy cows and humans. In terms of dairy cows, rBGH is injected by needle into cows every two weeks to increase individual animal milk production (by weight) from 10 to 15 percent. The effect on humans of rGBH is that it contains increased levels of insulin-like growth factor (IGF-1), which is identical in both the cow and human milk, and may be biologically active in humans. Insulin lowers blood sugar levels in humans, and increases cell proliferation. Evidence supports that IGF-1 from rBGH-treated cows may well promote cancer of the breast and of the colon in humans who drink such milk.

Do hormones lead to early signs of puberty?

Yes, coming from experimental evidence. It has been found that rBGH contains increased levels of insulin, which, in the diet of young children, can contribute to early signs of puberty. However, as mentioned, rBGH is not allowed for use in Canada.

What about antibiotics in milk?

Dairy cows may be treated with antibiotics, and if so are labeled clearly by the farmer. After treatment, the antibiotics must clear the cow’s system entirely- farmers must allow for appropriate withdrawal periods for each drug before the cow’s milk can enter the collection system again. As an effect on humans, antibiotics in milk may increase danger of bacterial resistances, cause allergic reactions and harm the intestinal flora of the person who consumed contaminated milk. However, milk is one of the most tested and regulated foods in Canada. A sample is taken from every load of raw milk picked up at each farm and before milk is accepted, the milk is tested for antibiotics. If antibiotic residue is found, the entire load of milk is destroyed. The farmer who contaminated the load is identified from samples taken at the farm and is severely penalized.

What is organic milk?

According to the Certified Organic Association of British Columbia (COABC), the term organic, “describes a process of food production that avoids the use of synthetic inputs such as chemical fertilizers, chemical pesticides, chemical growth regulators/hormones and antibiotics”.

Organic vs. Conventionally Produced Milk

As a finished product the regulations and safety checks are the same for organic and conventionally produced milk and therefore the end result for the consumer is identical in terms of safety, nutritional quality and health issues.
In BC the only difference in organic vs conventional milk might be seasonal flavour as there is only one organic farm in BC and seasonal feed changes may affect the flavour of the milk. In conventionally produced milk the milk is pooled to create a more consistent product.
In terms of nutrients, a study performed by a team at the Danish Institute of Agricultural Research showed organic milk has 50% higher levels of vitamin E, has 75% more beta carotene, and higher omega 3 essential fatty acids and antioxidants, which help beat infections. The team said organically reared cows benefit from having more room to graze than conventionally reared cows. Thus, it is worthwhile to drink organic if you aren’t getting these nutrients from other sources. The same study was not done on Canadian cows milk.

The Bottom Line: Do what you are comfortable with. If you can trust in the safety systems created by Health Canada and the Food Inspection Agency to test foods regularly then it seems both organic and conventionally produced milk are safe and nutritious.

Watch for the Eating for Energy segment every Tuesday on BCTV’s Noon News Hour!