It is an alluring idea. Some have even proposed that the quick fix already does exist – in the form of a mineral called selenium.

But the wishful thinking is a little premature. There is some evidence that the minerals in our food play a role in preventing cancer. More research is needed, though, before we can draw any conclusions.

The Minerals in Food

Food contains a wide range of minerals. We need some of them in large amounts. Other minerals are required in very small amounts.

Nutritionists refer to the minerals needed in large amounts as major minerals. Those that we need in small amounts are known as trace minerals or trace elements.

The most important major minerals are:

• calcium
• magnesium
• sodium
• chloride
• phosphorous
• potassium

There are many trace minerals. Scientists know a great deal about some of them, and very little about others. Some of the trace minerals include:

• copper
• chromium
• fluorine
• iodine
• iron
• manganese
• molybdenum
• selenium
• zinc

When it comes to minerals and cancer, research has focused only on trace minerals. None of the major minerals have been the focus of cancer research.

Too Soon to Tell

Most cancer institutions and foundations, including Committee on Diet, Nutrition, and Cancer (U.S.), made no recommendation about minerals. In general, the scientists found too little evidence for making judgment.
Some of them cited selenium and iron as the best-studied minerals. But though they found evidence that selenium may protect both humans and animals against some forms of cancer, the evidence was ruled preliminary.
Similarly, they found evidence that an adequate iron intake protects both humans and animals against cancer in the upper part of the digestive tract. But this findings, too, were considered inconclusive.

In this case, the Committee on Diet, Nutrition, and Cancer said that no conclusions could be drawn at all about the role of the following minerals in cancer prevention:

• copper
• zinc
• molybdenum
• iodine
• arsenic
• cadmium
• lead

It may surprise you to read the committee’s conclusions about these last three minerals – arsenic, cadmium, and lead. You may be aware that these minerals have long been linked to excessive cancer rates among workers who are heavily exposed to them. But occupational exposure to these minerals is many times higher than the levels that occur in food. For this reason, too, the committee declined to make any judgments.

The Selenium Story

Chances are that you have heard reports about the ability of selenium to prevent cancer. A few enthused promoters have inspired some people to take selenium supplements as a preventive measure.

The evidence that selenium helps to prevent cancer is promising but far from final. Research has shown, for instance, that:

1. Areas of the world where selenium intake is high have lower cancer rates than countries where the diet is low in selenium.
2. Blood selenium levels are higher in healthy people than in cancer victims.
3. Selenium added to the diet or drinking water of laboratory animals helps to protect against cancer-causing chemicals.

One problem with these findings is clear. Scientists can rarely know whether a cancer patient always had a low blood level of selenium. It is possible that the disease, once developed, cause a normal selenium level to drop suddenly.
Some research has yielded opposite results, showing no relationship between the selenium in the blood and the risk of cancer. But on the whole, the research on this mineral must be considered promising.

Oddly enough, there were once concerns that selenium might promote cancer. These fear have not been supported by the most recent research.
But research has shown that selenium can be toxic in other ways. Scientists hardly want to advocate a measure that will help prevent one disease but cause others instead.

By the way, I would be very grateful if you have some latest valuable information regarding this subject, never hesitate to write down on the comment board below.

( Next Story, the Part II )

Color is sometimes the key to judging the carotene in fruits and vegetables. Deep green and yellow vegetables. Deep green and yellow vegetables are usually very good sources of vitamin A. But lighter versions of the same foods are not. For example:

• Green asparagus is rich in vitamin A. The bleached white asparagus has about one-tenth as much!
• Romaine lettuce provides  four times as much vitamin A as iceberg lettuce.
• Yellow corn has more vitamin A than white corn.
• Green beans have more vitamin A than wax beans.

Here is my favorite piece of vitamin A trivia: frozen chopped broccoli has one-third more vitamin A than the frozen spears. I am willing to bet that the leaves in the chopped version make the difference. Their deep green color is a sure sign of vitamin A!

Though fruits and vegetables supply almost half of our vitamin A, other foods do have significant amounts. Meat, poultry, and fish provide about one-fourth of the vitamin A in our diet; diary products give another 15 % or so. Eggs and other foods supply a little less than 10 %.

But it is not known whether the vitamin A in most animal foods has any value in cancer prevention. That is why the Committee on Diet, Nutrition, and Cancer restricted its recommendations to fruits and vegetables. But in this regard, however, I suggest you to learn more about the potency of vitamin A in animal sources to fight cancer posted in BlogOfHealth.co.cc.

How Much Is Enough?

The Committee did not tell us exactly how much vitamin A to eat each day. But I will try to give you some rough guidelines.

For decades, nutritionists have recommended that we eat four or more servings of fruits and vegetables each day. It is a good idea to ensure that at least two or three of these servings are rich in vitamin A. I try to eat a fruit or vegetable rich in vitamin A at every meal.

I have been following my own advice for quite a while. So I can tell you that eventually you find your self eating fruits and vegetables rich in vitamin A almost automatically.

It’s Easy to Do

Here are a few simple ways to get your vitamin A intake where the experts think it should be:

1. Eat a salad every day, using lettuce that is dark green (such as romaine) and other carotene –rich ingredients such as tomatoes, green pepper, and carrots.

2. Drink juices daily that are high in vitamin A, such as apricot nectar, tomato juice, or vegetable juice cocktail.

3. Substitute sweet potatoes for white potatoes.

4. Keep a jar of dried apricots handy in the kitchen or on the table. If you can nibble during the day without gaining weight, keep a jar of apricots on your desk near your work area.

5. Top cereal with fruits rich in vitamin A.

6. Keep carrot sticks in cold water on hand as a snack.

7. Add parsley to recipes – and eat it.

8.Use tomato sauce instead of white sauce on pasta and main dishes.

9. Add chopped green pepper to chicken and tuna salads.

Of course, there are more exotic approaches, too. How about a high-carotene pizza using broccoli, green beans, and/or green pepper for “extras?” Or learning to cook in a wok. Stir-fried vegetables can be novelty, and they are healthful if you use only small amounts of good oil.

Here is another tip:  substitute sweet potatoes for white potatoes not just as a vegetable but in some of the many dishes made with potatoes. I used to make potato pancakes and potato scones; now I make sweet potato pancakes and sweet potato biscuits. And sweet potatoes are not the only vegetable suitable for baking. Pumpkin is another one.

Making the Most of Our Vitamin A

If you are nutrition-minded, you probably try not to lose nutrients in cooking.

But with vitamin A, you don’t have to worry. It is tough stuff; pretty much indifferent to water, heat, and even long periods of storage. Vitamin A does not dissolve in water, so it does not leach into water used in cooking.

Water not only doesn’t hurt vitamin A, but probably helps us to make the most of it. Cooking raw vegetables makes some nutrients more accessible to the body. Vitamin A is one of them.

Like vitamin D, E, and K, vitamin A is soluble in fat. This means that your body needs fat to absorb it. Will cutting back on fat leave you without enough to absorb vitamin A? The chances are almost nil.

It is amazing how little fat your body needs to absorb vitamin A. In fact, people who eat only one-fourth as much fat as the typical most of us show no signs of vitamin A deficiency. So cutting fat down to a moderate level, as recommended by the Committee on Diet, Nutrition, and Cancer, is not going to give you a deficiency of vitamin A. What it will do is make you healthier.

( to be continued )

I would drink my orange juice and eat my green peppers even if  it weren’t  for research linking vitamin C to prevention of cancer.

Some of my reasons are the same ones that bolster the advice to eat more fruits and vegetables that supply carotene.  Like these plant foods rich in vitamin A, foods rich in vitamin C are also low in saturated fat and sodium.

What’s more, fruits and vegetables that contain vitamin C are cholesterol-free. And they provide small to moderate amounts of dietary fiber. Eaten in large amounts,  the fiber in these fruits and vegetables helps to lower blood cholesterol levels.

There is more. Vitamin C is rarely recognized for its role in iron absorption. Yet we have known for many years that vitamin C helps the body to absorb iron.

The extent of iron deficiency in the United State and most industry countries have been greatly exaggerated, I believe, but there are probably more people taking in too little iron than is the case for other nutrients.

Because the body absorbs only about 10 percent of the iron taken in, factors that increase iron absorption are just as important as iron-rich food. In fact, some scientists believe that increasing absorption of iron, rather than boosting iron intake, is the key to improving iron nutrition. They may be right on target.

At moderate levels – such as 50 to 100 mg – vitamin C has been found to improve iron absorption by as much as 50 percent. Higher doses may result in even higher absorption. But very few of us truly need such as assist.

Vitamin C helps the body absorb iron in foods that are eaten at the same meal. The vitamin C in breakfast foods, for example, has little or no effect on the iron in foods eaten at lunch or dinner.

For some people, however, this is not good news. A small number of people have a condition that causes them to retain too much iron, which accumulates in various organs, causing health problems. People who have this condition should consult their physicians for advice about diet.

I would love to tell you that vitamin C will also help protect you from heart disease. But I cannot, because I am not at all convinced by these claims.

I have looked carefully at evidence that vitamin C lowers blood cholesterol levels. But I found other studies in which vitamin C supplements appeared to have raised the cholesterol level. Some studies show no difference. I really do not hold out much hope for an effect here.

But what more can you want from vitamin C? It does not have to play a role in prevention of every disease in order to be taken seriously.

In my opinion, vitamin C is as important today as it was two centuries ago, when the mysterious disease  called scurvy threatened the lives of sailors who spent months without fresh fruits and vegetables. It is hard to disagree with the advice to make more room for this familiar vitamin in our diets.