What do you think? Is organic milk really that different from conventional milk? Is it better for you? Let’s start by taking a look at the nutrition label. (Review these tips on how to read a nutrition label.)
|Calories||Fat (grams)||Sugars||Protein||Vit D (% DV)||Calcium (% DV)|
|Conventional Whole Milk (Prairie Farms)||150||8||11||8||25||30|
|Organic Whole Milk (Horizon)||150||8||11||8||25||30|
So, on the surface, there is no difference between the major nutrients in conventionally-raised milk and organically-raised milk. But what about that study that was in the news about the fatty acids?
Fatty acids in milk
A study published in PLOS One in December 2013 found that organic milk had less omega-6 fatty acids and more omega-3 fatty acids than conventional milk. Current research suggests that you want an ratio of omega 6:3 of around 2.3 in your diet, to help to decrease the risk of cardiovascular disease. Most people have a much higher ratio than that (so more omega 6, and less omega 3). The researchers for this article looked at some hypothetical diets for women aged 19-30 to see how a switch to organic dairy (which they found to have a lower omega 6:3 ratio) would change their overall fatty acid intake. They found that – with these hypothetical diets – switching to organic milk had about the same effect on overall fatty acid profiles as increasing consumption of conventional milk. But switching to foods lower in omega 6 fatty acids helped to change the ratio for the better. And the fatty acid content of milk can change with the season and with the cow’s diet. So, it turns out that switching to organic milk isn’t the magic bullet that will keep your heart healthy.
But what about hormones? Aren’t there hormones in conventional milk, but not in organic milk?
Hormones in milk
All milk contains hormones. Some conventional dairy farms do give their cows growth hormone (bovine somatotropin, BST, or rBST). This hormone increases milk production. But many dairy farmers have chosen to not give their cows this hormone, primarily due to market pressure from consumers. Check the label on the gallon of milk in your refrigerator. I’ll bet that even if it is “regular” milk, you’ll find a label that says “from cows not treated with rBST”. And a disclaimer that says “According to the FDA, no significant difference has been shown between milk derived from rBST treated and non-rBST treated cows.” Organic dairy farmers are not allowed to give their cows rBST.
So what about the hormone levels in the milk itself? Aren’t they different? According to a study published in the Journal of the Academy of Nutrition and Dietetics in 2008, they are a little different. But not in the way you might expect – conventional milk actually had less estradiol (a type of estrogen) and progesterone than organic milk. But the differences were so small, even though there is a statistical difference there really isn’t a biological difference.
|Estradiol (pg/mL)||Progesterone (ng/mL)|
Let’s try to put this into perspective. A pg is a picogram, or 1 trillionth of a gram. A ng is a nanogram, or 1 billionth of a gram. But what in the world does that mean? Here is a great graphic that helps to explain exactly how much hormone is in a few different foods, using M&Ms as a visual aid.
Now let’s do a little bit of math. The table above talks about hormones in terms of per milliliter. There are 236 milliliters in 1 cup. So if you were to drink 1 cup of conventional milk, that is 1176 picograms of estrogen, or 1.2 nanograms. In organic milk, there are 1.5 nanograms of estrogen in 1 cup. In the M&M example, the sliver of a M&M in a pint jar represents 0.85 nanograms in 3 ounces of beef. To extend the example to our milk, the conventional milk pint jar would have a little bigger sliver of M&M, and the organic milk pint jar would have about a half an M&M. Now look at the cabbage jar, on the far left. That jar is full! The average person has 13 full pint jars of M&Ms in their body, and the average pregnant lady has 178 pint jars of M&Ms (representing estrogen, of course) in their body.
So, really, is the difference between 1/4 and 1/2 of an M&M inside a pint jar that big? It certainly isn’t a big enough difference to make a biological difference to your body.
Okay. So let’s say you’re still with me through the math and the M&M reference. But what about antibiotics? Aren’t there antibiotics in conventional milk?
Antibiotics in milk
Nope. There are no antibiotics in milk. Period. On a conventional dairy farm, farmers can treat sick cows with antibiotics, under the direction of a veterinarian. These cows are separated from the regular herd, and their milk is discarded until they reach the end of the withdrawl period for the antibiotic. (The withdrawl period is the length of time that an antibiotic is secreted in the milk. Once the withdrawl period is over, there is no longer any detectable level of antibiotic in the milk.) On an organic dairy farm, the farmers are not allowed to use antibiotics to treat their cows.
Every time a tank of milk is picked up from a dairy farm, that milk is tested for antibiotics. Every single time. And it must test negative in order for the milk to be processed and get to the grocery store. If there are antibiotics found in the milk, the entire tanker of milk is dumped out, and the farmer is fined. If a farmer is found to have antibiotics in his milk too many times, the milk processor will stop accepting his milk.
So, what do you think? My family drinks conventional milk. I’ll be giving conventional milk to my son when he turns one. If you choose to drink organic milk, that’s a great decision for you and your family. I’ll respect your choice if you respect mine.
For more articles about dairy farming and milk production, check out this list.