Vitamin D comes from the sun. Higher levels of Vitamin D go with lower blood pressure, better insulin and glucose regulation, a healthier immune system, stronger bones, and less chance of colon, breast, and prostate cancers. The US Food and Nutrition Board has recommended that 200IU (5 mcg) of vitamin D is adequate for young to middle-aged adults, but recent research indicates that might not be enough.
It's hard to get enough vitamin D from food. Fortified milk has less than 100IU per serving. Vitamins for adults usually contain 400IU. But, if you are not getting enough sunlight, a vitamin pill may not give you enough vitamin D...
The most important source for vitamin D is the sun. We can make all the vitamin D we need (up to about 20,000IU in less than an hour) if we get enough UVB rays on enough of our bare skin. A light-skinned person living near Boston can typically get enough vitamin D by going outside in shorts and a short-sleeved shirt, without using sunscreen, 3 times every week from mid-March to mid-October for 5 to 10 minutes between 11AM and 2PM. And be able to store enough to last through the winter, when there is not enough UVB light for making vitamin D. Further north, the "vitamin D winter" lasts longer. Closer to the equator, a person needs less time in the sun. Sunscreen blocks UVB rays -- that's its job. Even an SPF8 sunscreen cuts production of vitamin D by 95%. Darker-skinned people may need 5 to 10 times longer in the sun, depending on the amount of melanin (the dark pigment) in their skin. Older people may not be able to make vitamin D in their skin as quickly. People with liver disease may not be able to produce enough of the provitamin-D3 that the skin uses to make vitamin D. Obese people may need more vitamin D because so much of it gets stored in body fat. There are a lot of variables.
Exposing your arms and legs to the sun for 20 minutes at the right place and time could get you a dose of 20,000IU of vitamin D -- much higher than we get from food. This means food is not the most important source of vitamin D. Which makes it hard to calculate an RDA for vitamin D from food. But, if people spend more time inside and more of their outdoor time using sunscreen, they'll have to get it from foods and supplements, or risk their health.
So get a little noonday sun every day for as long as summer last. In the Northern hemisphere, Vitamin D summer lasts until October or November, depending on how far north you live. It has already already begun in the northern Australia, and continues all year long in the tropics.
How much vitamin D is too much? Vitamin D toxicity has never been observed in people getting their vitamin D from the sun. Most people are unlikely to have any problem from as much as 10,000 IU/day from supplements. But some medical conditions (lymphoma, sarcoidosis, tuberculosis, and primary hyperparathyroidism) can cause a bad reaction to vitamin D pills.
Tuesday, August 19, 2008
Vitamin D, the Sun, and your Heart
Posted by Family Nutritionist at 8/19/2008 10:14:00 AM 2 comments
Labels: blood sugar, health, heart disease
Monday, August 18, 2008
Obesity and Psychological Distress
Posted by Family Nutritionist at 8/18/2008 10:01:00 PM 1 comments
Thursday, August 14, 2008
A berry good snack for the kids
At some point, the kids will get bored of even the most luscious farmstand peaches. Here's a quick, icy snack they'll love. Because the milk turns blue.
Icey Berry and Milk Snack
1/2 cup frozen strawberries
1/4 cup frozen Maine or wild blueberries
1/4 cup skim milk, or less if you run out of room in the bowl.
Surprisingly, this will all fit in the same 6-oz bowl.
Put about 1/2 cup large frozen strawberries in a bowl. This will only be 3 or 4, with a lot of empty space between. Pour in 1/4 cup frozen tiny Maine blueberries. They'll fit between the strawberries. Shake them down to the bottom of the bowl. Now add the milk.
Immediately, the milk will freeze into a skin around the berries. Cut or mash the strawberries with a spoon to expose new surfaces for the milk to freeze on. Explain that this is ice milk. Tell them the story about how, when your mother was little, the milkman left milk on the back porch every morning, how some winter mornings the cream floated up to the top of the milk bottle and froze, and how their grandmother's mother stirred it up with vanilla so they could have ice cream with breakfast. The kids will ooh and aah, splash purple milk on the kitchen table, and be perfectly delighted with their special afternoon snack. Notice how you haven't gotten out the sugar bowl. That was easy. Don't forget you need a snack, too.
Posted by Family Nutritionist at 8/14/2008 04:08:00 PM 0 comments
Who taught Michael Phelps how to eat?
12,000 calories and no fruit on the plate. As usual, Bix has made me think. Michael Phelps' diet doesn't seem to be hurting his Olympic performance. But it's surprising to see so little produce in his diet. I heard Bob Costas recite the breakfast menu, but I was surprised when I saw the full daily menu in print....
Breakfast: Three fried-egg sandwiches loaded with cheese,
lettuce, tomatoes, fried onions and mayonnaise. Two cups of coffee. One five-egg
omelette. One bowl of grits. Three slices of French toast topped with powdered
sugar. Three chocolate-chip pancakes.
Lunch: One pound of pasta. Two large ham and cheese
sandwiches with mayonnaise on white bread, plus 1,000 calories of energy drinks.
Dinner: One pound of pasta, an entire pizza and even more
energy drinks.
And, according to a 2005 IGN interview, a daily multivitamin.
As a parent, I spend time explaining to my kids why fruit and vegetables make better snacks than cookies, why we don't eat candy when we're hungry, how a sweet-potato muffin can be a better choice than a 4-oz bagel, and why we like to have lots of vegetables during dinner, not just a really big pizza. I explain to them that, if they want to grow up healthy and have the energy and strength to run around and have fun, they need to eat the way I've taught them. Apparantly, that's not strictly true. Michael Phelps' only vegetables come on his morning fried-egg sandwiches, and perhaps in the unspecified pasta sauce, and there's no fruit in his diet at all. Yet he seems to have grown up big, with plenty of strength and energy, and have no health problems -- at least nothing that would interfere with him swimming freestyle and butterfly faster than anyone else in the world.
Of course, even if his foods are low in certain nutrients, he's eating so much that he may be getting what he needs of A, B, C, D, and E and most of his minerals. But what about blood sugar spikes, oxidative stress, arterial plaques, risk of colon cancer, fiber, antioxidants, and omega-3 fatty acids? I didn't worry much about these things when I was 23, either. Even though I wasn't quite as focussed on school as Phelps is on swimming.
Until they ask, I'm not going to confuse the kids by explaining why Michael Phelps' diet is not designed for them -- they aren't 6'4" and 195 pounds, and don't swim 9 miles a day. So they don't eat unlimited "seconds", and are not going to substitute cookies for carrots. Even Michael Phelps doesn't eat cookies. Only chocolate-chip pancakes.
Posted by Family Nutritionist at 8/14/2008 09:13:00 AM 0 comments
Wednesday, August 13, 2008
Sweet Potato Orange Muffins
Sweet Potato Orange Muffins
A moist, rich muffin with a pumpkin-pie flavor
Recipe By: Family Nutritionist
Servings: 16
-= Ingredients =-
2 c Whole wheat flour
2 ts Low-sodium baking powder
2 ts Baking soda
1 1/2 ts Cinnamon
1/2 ts Nutmeg
1/2 ts Allspice
3/4 pound Sweet potatoes ; cooked, mashed/pureed
1/2 c Firmly packed brown sugar
4 large Egg whites
1 c Orange juice
1 medium Carrot ; shredded
1 ts Vanilla
-= Instructions =-
Lightly grease 16 muffin pan cups or line with paper liners. In a medium bowl, flours, baking powder, baking soda, and spices. In a large bowl, mash sweet potatoes. Add brown sugar, eggs, orange juice, carrot and vanilla. Mix well. Add dry ingredients to sweet potato mixture and stir until combined. Fill muffin cups 3/4 full with batter and bake at 400 F for 15 to 20 minutes or until tops are brown. Let cool slightly and remove from pan. Serve warm. Makes 16.
Serving: 1 muffin (77g), Calories: 113: Fat: 0g (4% of Cals): Sodium: 178mg
Protein: 3g, NetCarbs: 21, K: 242mg
SatFat: 0g, PolyFat: 0g, MonoFat: 0g, Chol: 0mg
TotCarbs: 24g, Fiber: 3g, Sugars: 9g
DASH: Vegetables: 0.2: Fruits/Juices: 0.1: Dairy: 0.0: Grains: 0.9: Meat/Fish: 0.0: Seeds: 0.0: Fats: 0.0: Sweets: 0.5
USDA: Vegetables: 0.1: Fruits/Juices: 0.0: Dairy: 0.0: Grains: 0.9: Meat/Fish/Seeds: 0.1: Fats: 0.0: Sweets: 0.5
Based on a recipe by: Womans Day Low Fat Meals, June 1995
Posted by Family Nutritionist at 8/13/2008 07:30:00 AM 2 comments
Tuesday, August 12, 2008
Antioxidant chocolate and cinnamon treats
Blog posts are archived forever, but they seem ephemeral. So I wrote a knol encapsulating a lot of the thinking that went into developing the chocolate-cinnamon treats I posted about in June. Since I just figured out ensure these patties have a good texture, I also wrote a knol about keeping chocolate's temper. "Heat gently" means more gently than I had thought!
Posted by Family Nutritionist at 8/12/2008 11:46:00 AM 2 comments