If you drop about a roll and a half of Mentos mints into a 2-liter bottle of Diet Coke, you'd better run like hell because the Mentos causes the Coke to erupt into a beautiful, 15-foot high, sugary-sweet Coca Cola geyser.

The Diet Coke/Mentos phenomenon.

Talk to five chemists and you'll get five explanations as to why it happens. Regardless of the reason, it works.

Similarly, if you turn off all the lights and start chewing – biting – some Lifesaver Wintergreen Mints, your mouth will be filled with weird green sparks.

Again, I'm not sure anyone knows the explanation, but it's not an urban myth.

While these examples of "food magic" are great for impressing your 15-year-old date, they're little more than parlor tricks.

Fortunately, I know some other bits of food magic that are a little more practical. Here are 5 of them:

Grapefruit Juice and Supplements

Intestinal cytochrome P-450 is a busy little enzyme. It metabolizes an incredible number of the drugs we ingest.

If, however, you inhibit cytochrome P-450, it doesn't metabolize the drugs as well, resulting in higher concentrations of said drug.

Certain naturally occuring flavonoids and other chemicals inhibit cytochrome P-450, and they're found in high levels in broccoli, cabbage, spinach, onions, garlic, and parsley.

However, none contain higher amounts of these inhibitory enzymes than grapefruit juice, which can inhibit enzyme activity by as much as 84% (according to one study). In fact, many pharmacists will warn you not to take certain prescription items with grapefruit juice, as it may result in undesirably high levels of the drug.

However, if you're careful, grapefruit juice can be used with any number of supplements to either intensify the effect, or make the effect last longer.

While Biotest doesn't have lab information on all of the product ingredients that are metabolized by cytochrome P-450, the enzyme is surely involved in metabolizing forskolin and yohimbine.

Personally, I've found the effects of Carbolin 19, HOT-ROX Extreme, and, unless it's my imagination, Spike, to be intensified by taking them with 8 ounces of grapefruit juice.

If you try it, use a whole lot of caution!

Vitamin C and Barbecued Meat

You know it isn't good for you, but you eat it anyhow. Hell, it's summer, so you'd have to be namby-pamby to pass up a barbecued burger or steak.

Still, it doesn't hurt to use some protection.

That's why, before your lips even touch a piece of charred meat, you should ingest some foods high in Vitamin C.

Here's the problem:

When you cook meat, fat drips off and hits the coals. The hot coals form a carcinogen known as benzopyrene, which floats up in smoke and embeds itself in your burger. Likewise, when the hot grill comes into contact with the meat, other carcinogens known as heterocyclic amines are formed.

To make things worse, if your host is grilling hot dogs or some other preserved meat, they're soaked in nitrates. Once nitrates are eaten, they combine with amines in the mouth and gut to form nitrosamines, which are yet another class of carcinogen.

Put them all together and you've got...well, bad news. Granted, the odds of developing esophageal or gut cancer from just a few servings of burnt meat are very low, but why take a chance, especially since it's summer and you'll no doubt be eating more charred meat than a hungry Neanderthal?

Soooo, when you know some charred meat is on the way, eat something high in Vitamin C before so much as touching your lips to a burger. Foods that are high in Vitamin C that might reasonably go with a barbecued food include red peppers and broccoli.

Barring that, pop a Vitamin C tab before you chow down.

Protein Before Carbs

If you're like the majority of Americans, you usually feel like nodding off about 2 or 3 in the afternoon. It's a wonder that America gets any work done during the mid-afternoon.

Other cultures seem to have realized this, and that might explain the mid-afternoon siestapracticed in Spain and Mexico.

The reason for this sleepy lapse in productivity, however, is probably dietary.

If you eat carbohydrates, or even a salad with some croutons before sinking your teeth into some protein, you set up a very disadvantageous chemical scenario.

By eating carbohydrates first in your meal, you elevate insulin levels so that any amino acids you eat subsequent to the carbs will be shuttled off into the liver and muscles.

Unfortunately though, insulin doesn't have this shuttling effect on the sleepy-time amino acid tryptophan.

And, since insulin has shuttled all the other amino acids to far-off destinations, tryptophan is left all by its lonesome to cross the blood-brain barrier and cause an increase in serotonin, which is a hormone that causes drowsiness.

If however, you were to eat some protein before eating any carbohydrate, all those amino acids would compete with tryptophan to cross the blood-brain barrier. Since tryptophan is kind of big and bulky as far as amino acids go, it would "lose out" to other smaller, more "nimble" amino acids and not be able to get to the brain.

Consequently, tryptophan wouldn't be able to increase the production of serotonin and you wouldn't get sleepy.

Take home lesson: If you want to avoid a mid-afternoon crash, don't take a single bite of carbohydrate until you've eaten some protein.

Vinegar and Salad

Glycemic index (GI) researchers have discovered that adding vinegar to a food will dramatically reduce its GI.

If the GI of a food is low, it means, in very general terms, that the food won't cause much of a rise in blood sugar, and if blood sugar isn't affected greatly, the pancreas won't secrete as much insulin.

In turn, if the insulin response is low, carbs and fats won't be shuttled off to storage areas (like that fat repository around your waist!).

As such, if you're fat conscious, it's a good idea to mitigate the GI of foods. If you've been invited over to dinner and you're faced with a pasta feast without hope of escape, pour vinegar and oil salad dressing over your salad. It'll offer some "protection" from your coming pasta feast.

Broccoli and Tomatoes

One in six of us male-types are predicted to get prostate cancer some time during our lives. While it's thought to be an old man's disease, it's such a slow-growing cancer (most of the time) that it probably starts 10 to 20 years before symptoms pop up.

Given that, it's probably a good idea to adopt a pro-active cancer-fighting stance, and a good first step is eating broccoli and tomatoes together.

While broccoli and tomatoes are good cancer-fighters all on their own, a recent study has found that combining them leads to a synergistic effect. Together, they're up to 13 times more powerful in inhibiting cancerous growths than they are on their own.

I'm hardly a recipe guy, but this is a pretty simple one:

Marinated Broccoli and Tomato Salad

1 lb Broccoli
1/4 lb Mushrooms, fresh
3/4 c Black olives, pitted, drain
1 c Tomatoes, cherry

Dressing

1/3 c Olive oil
1 tb Vinegar, white wine
1 tb Lemon juice
2 tb Parsley, fresh chopped
1 Onion, green, minced
1 Garlic clove, minced
1/2 ts Salt
1/4 ts Pepper, freshly ground

1. Trim flowerets from broccoli, you should have about 1 quart.

2. Drop broccoli flowerets into boiling salt water for 1 min. or just until they turn bright green; drain.

3. Trim mushroom stems to 1/2-inch.

4. Combine broccoli, mushrooms, olives and tomatoes in bowl.

5. Measure oil, vinegar, lemon juice, parley, onion, garlic, salt and pepper into small bowl. Whisk until blended.

6. Pour dressing over vegetable mixture.

7. Turn gently to coat vegetables. Cover and refrigerate 3 or more hours until ready to serve.

Hopefully I've given you some info you can use. While none of the 5 items I discussed are as dramatic as the Coke and Mentos things, they're nice tricks that will help you manage your health and your waistline.