You Ask, I Answer: Wasabi

Does wasabi contain any healthful properties?

-- Peter Aitken
(city withheld), MA

Depends on which wasabi you are referring to.

Traditional wasabi (pictured at right) is obtained from the wasabia japonica plant.

Its underground stem is grated moments before consumption, since exposure to air significantly decreases its powerful taste.

This form of wasabi -- commonly referred to as "wasabi root" -- is a good source of potassium, calcium, vitamin C, betacarotene, and quite a bit of phytonutrients and antioxidants.

Wasabi root is also a source of isothiocyanates -- compounds found in relatively high quantities in raw broccoli and raw cabbage that have been linked with tumor inhibition.

However, the wasabi served alongside sushi at practically every Japanese restaurant in the United States is the end result of mixing water and a dry powder made up of horseradish, dry mustard, and some food coloring.

There is nothing inherently unhealthy about this knockoff, but it also lacks the nutrition of the real deal.

Faux wasabi is higher in sodium, though. Two teaspoons of the mean green machine add 200 milligrams of the mineral to your meal. That same amount of real wasabi would only add up to 2 milligrams.

Numbers Game: Friendly Fire

Researchers at England’s Institute of Food Research concluded that our bodies absorb ____________ times more betacarotene from cooked carrots than raw carrots.

(NOTE: “Cooked” mainly refers to steaming, which retains more nutrients than boiling).

a) 85%
b) 500%
c) 275%
d) 100%

Leave your guess in the "comments" section and come back on Monday for the answer.

You Ask, I Answer: Carrots

How many carrots do you have to eat before your skin turns orange?

Or is this an old myth?

-- Anonymous
Via the blog

Although countless myths surround food and nutrition, it is indeed true that eating too many carrots will turn your skin temporarily yellow or orange.

Remember, betacarotene (the plant form of Vitamin A) is fat-soluble, meaning it is stored in adipose tissue (fat cells).

Our bodies can only store a given amount at a time. Unlike with a water-soluble vitamin (like C or B6) excess amounts of Vitamin A are not quickly eliminated in urine. Instead, they are contained in the body and begin to affect our pigmentation.

There is actually a term for this condition – carotenaemia.

So just how many carrots do you need to eat in order for color changes to take place.

Consider this.

The Recommended Daily Intake is set at 5,000 International Units. A cup of sliced carrots provides approximately 30,000 International Units!

This is not to say that having a cup of steamed carrots with dinner once a week is cause for concern.

However, a cup of carrots every day for several weeks will definitely result in an orange tint to your skin color.

All-Star of the Day: Carrots

Although today’s A-list vegetables are of the dark, leafy, and green variety, let’s not forget the mighty carrot.

These colorful root vegetables are super abundant in antioxidants known as carotenoids. Remember, anytime you see the word antioxidant, you need to associate that with “cancer-fighter”.

One famous carotenoid found in carrots is beta-carotene, which gets turned into Vitamin A in our livers. And what is Vitamin A good for? A lot of things, including keeping lungs, eyes (Vitamin A helps absorb light into our eyes), and skin healthy.

A 14-year Dutchy study published in the Journal of the American Medical Association in 2005 found that people with high risks of developing macular degeneration of their eyes -- the leading cause of blindness for adults over 60 in the United States -- had that risk decreased by 35% when they consumed diets high in beta-carotene.

Carrots have SO much beta-carotene that the body can’t turn all of it into Vitamin A. The rest stays in its natural antioxidant form and sticks around as an immunity-system booster, making sure any free radicals (cancer-causing chemicals) are slowed down.

Next time you’re grocery shopping, keep in mind that the more orange the carrot, the more beta-carotene it contains.

That’s not all. In 1989, a team of biochemists at Kyoto Prefectural University of Medicine in Japan discovered that a carotenoid in carrots known as alpha-carotene played a significant role in slowing down the growth of many tumors.

Meanwhile, falcarinol, which is actually a natural pesticide produced by carrots, has been found to be quite powerful in lowering our risk of colon cancer.

One cup of carrots only clocks in at 30 calories but provides 650% of our Vitamin A and 20% of our Vitamin C needs, 4.5 grams of fiber, and 12% of our recommended potassium intake.

Before you break out the baby carrots and fat-free dip, though, here is some Nutrition 101.

Vitamin A is a fat-soluble vitamin. Two important things to take from that. First, fat-soluble vitamins are stored for longer periods of time than water-soluble ones.

Vitamin C, for instance, is water-soluble. Have too much in one day and the body will urinate the excess rather quickly. It is important to consume water-soluble vitamins in a consistent fashion, since the body isn’t able to hold on to them for very long. Have a lot of Vitamin A one day and not as much the other and you’re still OK, since the body can hold it in the liver for a few days.

Most importantly, though, the body needs fat in order to absorb fat-soluble vitamins. So, when eating carrots, pair them up with healthy fats (whether it’s dipping baby carrots into hummus or adding some avocado to your spinach and carrot salad).

If you can’t get into the whole baby carrot snack habit, worry not -- cooked carrots offer even more nutrition than their raw counterparts. Research has shown that heat increases the antioxidant activity of Bugs Bunny’s staple.