We are so fortunate to have Dr. Val Jones to join us again as the MIND coach for the Triple Play Fit Family Challenge. Dr. Val is available to answer your nutrition questions. Email her directly at firstname.lastname@example.org or leave a comment below.
1. Should parents be concerned about hormone levels in milk? Is there an advantage to buying organic milk?
All mammals release trace amounts of hormones into their milk. Cow's milk naturally contains a small amount of bovine somatotropin (bST) which is a protein that is quickly broken down by our stomachs when we drink milk. Some farmers give their cows additional amounts of the hormone to stimulate milk production. This rbST (or BGH) is virtually identical to naturally occurring cow hormones and the decades of research we've collected has been reviewed by the FDA (Food and Drug Association), WHO (World Health Organization), NIH (National Institutes of Health), AMA (American Medical Association), and ADA (American Dietetic Organization) - and all agree that rbST is safe for human consumption in the levels it occurs in cow's milk. Interestingly, studies have shown that milk hormone levels in organic milk is essentially identical to levels in regular milk. There is therefore no advantage in buying organic milk insofar as hormones are concerned.
I believe that cow's milk is safe and nutritious for kids (so long as they have no milk allergies or lactose intolerances). The milk/hormone scare is kind of an urban legend, so I wouldn't be too worried about it. Your girls haven't suffered any harm from drinking regular milk - and it's great that you all enjoy the skim variety, by the way. Lower calorie options can help you maintain your weight over your lifetime.
For more information about milk and hormones please check out this helpful link full of research resources: http://www.nationaldairycouncil.org/SiteCollectionDocuments/footer/FAQ/food_safety/MilkandHormonesFactSheetAugust2008.pdf
2. How much water should my 9 and 11 year olds drink?
Your instinct is correct that 8 glasses per day may be excessive for your kids. Even though 8 glasses of water/day is recommended for adults as a rough rule of thumb, our actual water needs vary a lot from day to day. Water requirements depend on how much we take in from other sources (food and drink), what the environment is like (hot/humid?), if we're sweating or exercising, and how much we weigh (a smaller person needs less water of course).
Unless you're exercising very vigorously (you may need to rehydrate before you feel thirsty), thirst is a reasonable guide for when to drink. I know that sounds pretty obvious, but sometimes we have to just listen to our bodies. As a double check to make sure we're taking in enough fluids, we can also rely on our urine color. A nicely hydrated person (or child) has light yellow to clear colored urine. Concentrated urine (dark yellow or orange) means you're not getting enough fluid.
Thanks again for your questions!
All my best,