Tuesday
May082012

Vitamin A

The quick answer:  At a basic level nutrition reform is quite simple:  Eat less sugar, lots less, and eat more vegetables, lots more.  It's that simple.  And be sure to eat something orange.

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A Brief History of the Vitamin Business

This year marks a historic moment in nutrition:  The term “vitamin” was coined exactly 100 years ago.  The discovery of the 13 known vitamins between 1910 and 1941 was the most exciting nutrition event of the time.   A longer look at our romance with vitamins reveals the difficulty our society has with nutrition:

  1. Thoughtful physicians make a connection between disease and dietary deficiency.  The first instance was beriberi.   The advent of polished white rice led to beriberi (caused by B-1 or thiamine deficiency) among the upper class in Asia.  Before this British had linked scurvy to the poor diet of their sailors.
  2. Scientists then discovers the exact dietary deficiencies:  Vitamin C for scurvy, B-1 for beriberi, vitamin D for rickets, vitamin A for poor vision, and vitamin B-3 for pellagra (a disease that ravaged the poor people of the South).  Later certain birth defects are linked to insufficient folic acid (the preform of vitamin B-3).
  3. Laboratory researchers, in the hope of better treating these diseases, develop synthetic forms of the vitamins naturally found in whole foods.  This reflects a blind faith that man can reinvent Nature.
  4. Businessmen package the synthetic versions of natural vitamins in pill form that doctors can prescribe for the treatment of disease.
  5. To grow their business, these pills are offered to the general population without prescription or doctor guidance in the false belief they’ll promote good health. 

Bottom line:  In the Industrial Revolution we were good at making money from scientific discoveries such as vitamins, but we were slow to learn an important lesson—if you desire to be healthy, the best source is still Mother Nature.

Carotenoids and Vitamin A

The retina of your eyes requires vitamin A (or retinal) to function.  The body makes vitamin A from the many carotenoids in a healthy diet.  Of the carotenoids, beta-carotene—the orange pigment in carrots—plays a key role but others may also be important.   The role of carotenoids in eye health was discussed in this post.

There are hundred of different carotenoids in a healthy diet and though we don’t understand all they do, we know they act as antioxidants.  We discussed the critical role of antioxidants in the posts titled Staying Alive and Aging with Grace

Vitamin A enhances the immune system and aids reproductive health as well.  It’s also preventative of infections, including the respiratory and diarrheal infections common to children.  Worldwide, vitamin A deficiency takes a terrible toll in child mortality and blindness.  Carotenoids are protective of heart disease and certain cancers.

Such deficiency is uncommon in the U.S. but there is chronic insufficiency.  Because we eat so few vegetables, carotenoids constitute one of the major dietary insufficiencies for Americans.  One goal of this blog is to remedy carotenoid insufficiency by eating more vegetables.  We earlier addressed this with the post, In Defense of Veggies.  

The Simple Truth

At a basic level nutrition reform is quite simple:  Eat less sugar, lots less, and eat more vegetables, lots more.  It's that simple.

Vegetables perform many functions but they're our primary source of carotenoids.  Authorities recommend 4-5 daily servings.  Americans, if you don’t count French fries, average about 1 serving daily.  This is such a big problem it’s the subject of 8 of our 52 Healthy Changes.   You’ll notice much less attention to fruit—also important but so much easier to include in the diet.  When you plan your vegetables, think about colors.

Eating red:  Lycopene, an important carotenoid, gives tomatoes and other red fruits and vegetables their color.  There is evidence that lycopene is protective of certain cancers, including prostate cancer.  Cooked tomatoes are our richest source of lycopene and last week’s recipe Real Spaghetti Sauce gave a recipe. Our menu goal is one serving of tomato sauce per week.

Eating green:  Last year in the post titled Seeing Green, we introduced green carotenoids like lutein and zeaxanthin and discussed their role in reducing the risk of cataracts and macular degeneration.   We also looked at their importance in the post The Joy Of Salads and suggested a green salad most days.

Eating orange:  This week we look at how to include the orange carotenoids in your diet.  Foods rich in the orange carotenoids:

  • Carrots
  • Sweet potatoes
  • Any yellow or orange quash
  • Oranges (the beautiful wife puts OJ on her breakfast compote)
  • Apricots
  • Mangoes
  • Papaya

A good way to do this is to eat an orange fruit and vegetable each day.  Keep this rule in mind when writing your weekly menu and shopping list.  If healthy food isn't in the house, it can't be eaten.

 Please comment:  What is your favorite orange vegetable.  Have a recipe you want to share?

Need a reminder? Download our Healthy Change reminder card. Print and fold, then place in your kitchen or on your bathroom mirror to help you remember the Healthy Change of the week.

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Reader Comments (7)

Mangoes!
And I'm guessing the sugary, dried version from Costco isn't quite as healthy as the real thing?

May 8, 2012 | Unregistered CommenterKristen

We eat carrots like they are going out of style at our household (5-10 pounds a week for two adults and a toddler). One of my favorite ways to eat them is to roast carrots with a chicken. Fill the roasting pan space that is not being used by chicken and rack with carrots and an onion or two. When the chicken is done. Take the carrots, onions, and chicken drippings and puree them with a bit of broth to make a gravy. Eat it with your chicken. It is amazingly good. I don't think I will go back to regular gravy again.

May 8, 2012 | Unregistered CommenterLady Susan

You specify that cooked tomatoes are rich in lycopene. Is there not as much found in raw tomatoes? Is there something about cooking them that releases the vitamins? I've been under the understanding that cooking--or maybe more specifically overcooking--fruits and vegetables decreases the efficacy of the vitamins. Is that not true, or could it be true of some vitamins and not others?

May 9, 2012 | Unregistered CommenterTom

Hi Tom

Thanks for your question. Lycopene is equally present in both raw and cooked tomato products but there is evidence that it's more bioavailable when cooked, or when combined with oil. Thus tomato sauce that is cooked for several hours with EVOO is a health bargain that we try to include in at least one dinner weekly.

The good effects of cooked tomatoes should not rule out the use of raw tomato products as the chemistry of lycopene is the body is not fully understood. We do know that lycopene is a workhorse antioxidant important to the protection of cell membranes and that it has anti-tumor properties also.

May 9, 2012 | Unregistered Commenterskip hellewell

When they are in season, those Cuties oranges that you can buy by the box at the grocery store are a super snack for us (meaning me, my husband and our young boys 3 and 1). They are easy to peel and don't contain any seeds. I can easily eat a couple in a sitting and my boys like them too as a snack.

I agree it is easier to eat fruits than veggies each day and this is something I'm working on. Hopefully some other readers have good suggestions for preparing the other orange vegetables.

May 9, 2012 | Unregistered CommenterLisa

Getting enough orange vegetables is a challenge for my family. Mostly because I forget to purchase a variety at the store. But, we really do enjoy them, and this post reminded me that I need to just get them put on my menu. Here are some of our favorite ways to eat them when we do remember...

Carrots: oven roasted in a bit of olive oil with kosher salt, or steamed in the microwave with button mushrooms and dill.

Sweet potatoes: mashed with a bit of butter and a sprinkling of coarse sugar, or roasted into fries with a dash of kosher salt.

Yellow squash: My kids like these sauteed with zucchini from our garden.

Apricots: We have access to many apricot trees, so we bottle and dry these to eat all year. My mom also bottled apricot puree, and then added the puree to orange juice. It was a great way to extend the juice for our large family.

May 10, 2012 | Unregistered Commentervalena

How about orange peppers grilled with a little olive oil and salt. Works well for all peppers! They are good as leftovers too and in sandwiches. We love plain baked yams (sweet potatoes)...with a little butter and salt and pepper. We had some on Mother's Day.

May 15, 2012 | Unregistered CommenterNancy O

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