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Vitamin Poisoning

Are you taking too many vitamins? Do you know the harmful effects of consuming excessive vitamin and mineral supplements?

Vitamin deficiency syndromes are uncommon in Western countries. Overeating is more prevalent than starvation.

Then why 30 per cent of the population consumes over-the-counter vitamin and mineral supplements?

The answer is simple. They hope to improve their health and prevent disease. For healthy individuals, experts recommend the following vitamin supplements:

1. folic acid (400 ug/day) – reduces the risk of heart disease, colon and breast cancer and birth defects during pregnancy,
2. vitamin B6 (2 mg/day) – keeps homocystein levels down and reduces the risk of heart disease,
3. vitamin B12 (6 ug/day), – same as B6 plus reduces the risk of cancer,
4. vitamin D (400 IU/day) – minimizes risk of osteoporosis and fractures,
5. omega-3 fatty acids (1000 mg/day or eat fish two to three times a week) – reduces the risk of sudden heart attack by 50 to 80 per cent, and
6. a multivitamin will ensure an adequate intake of other vitamins for which the evidence of benefit is indirect.

Regular use of vitamin E and C remains controversial.

Recently, the UK Food Standards Agency reviewed 36 vitamins and minerals and discussed the potential harms that can come from consuming such supplements. This information is summarized in the Canadian Medical Association Journal by Dr. Eric Wooltorton.

If a person consumes high doses of some vitamins, especially taking them on a regular basis, may suffer from side effects. The side effects generally involve the liver, stomach and bowel. Such as: nausea, vomiting, diarrhea, liver damage, visual problems, nerve damage etc.

The CMAJ article says that minerals taken as supplements can also be toxic. For example:
-magnesium can cause diarrhea at doses above 400 mg/d;
-phosphorus can cause diarrhea at doses above 750 mg/d, and mild nausea and vomiting at lower doses;
-iron can cause constipation, nausea and vomiting, reduced zinc uptake, and iron overload;
-zinc can cause nausea and vomiting, immunosuppression and impaired copper uptake; and
-selenium at doses above 0.91 mg/d can cause brittle hair and nails, peripheral neuropathies and gastrointestinal upset.

Is it possible to prevent vitamin and mineral toxicity?

Yes, regular screening enquiries about the use and dose of vitamin and mineral supplements may help to optimize a patient’s nutrient intake and avoid potential harm from inappropriate use of supplements (e.g., intake of beta carotene by smokers may increase the risk of lung cancer), says CMAJ article.

The article says that the European Union recently moved to adopt strict labeling standards for vitamin and mineral supplements, including having manufacturers list the percentage of a person’s daily intake that is represented by one dose of the product, as well as toxicity warnings when they are appropriate.

Will Canada adopt similar standards? asks Dr. Wooltorton. Only time will tell. In the mean time, do not over dose yourself with vitamins and minerals. Eat a healthy diet, eat lots of fruits and vegetables, exercise regularly and take vitamins as described above.

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Skin Cancer in Children

Do children get skin cancer?

Yes. Approximately two per cent of melanomas (the worst of the skin cancers) occur in patients under the age of 20 years, and about 0.4 per cent of melanomas occur in prepubertal children, says an article in the New England Journal of Medicine (NEJM).

For adults, the Canadian statistics show that for males, the incidence rate of melanoma has tripled since the late 1960s, from 3.2 per 100,000 population in 1969 to an estimated rate of 10.5 per 100,000 in 1998. For females the rate has varied a bit but still is on the rise.

It is known that high exposure to sunlight during childhood sets the scene for higher rates of melanomas as an adult. And history of sunburn as a child is a risk factor. Skin damage and probably skin cancer increases with one’s level of total cumulative exposure to the sun and number of sunburns, says an article in the Canadian Medical Association Journal (CMAJ).

People get more exposure to sunlight in July and August (just the way we are experiencing now) than at any other time of the year. Children are no exception. They spend more time outdoors than adults.

People with fair skin, such as those with Scandinavian ancestry, are more prone to sun damge than people with darker skin, says the CMAJ article. The death rate from melanoma also continues to rise about two percent annually.

What can we do to combat the rising incidence and death rate from melanoma?

According to Ca – a Cancer Journal for Clinicians, we need a three pronged approach to effectively deal with this problem:

1. Public awareness and understanding of melanoma must be improved.

We have to remember that melanoma is probably the most clear-cut case of a cancer where early detection and treatment are key to improving prognosis. New York University has developed ABCDs of early clinical signs of melanoma recognition. Public should be aware of these signs:

-Asymmetry
-Border irregular
-Color uneven
-Diameter greater than 6 mm.

2. Better methods are needed for identifying those at highest risk.

This can be achieved with more research. Hopefully, the future will bring more specific genetic and/or biologic risk models to make this exercise worthwhile.

3. More specific therapies for melanomas need to be developed.

Most early melanomas can be treated with wide surgical excision. But prognosis drops dramatically when the tumor has spread. There is no curative treatment available for advanced melanoma.

While we are waiting for scientific break through in many areas of melanoma, we can try and prevent melanoma by protecting against sun exposure and sun burn. Natural protection (shade) is considered the best protection. And sunscreen (SPF 15 or higher) should be adjunct to natural protection.

Wear sun protective clothing (tightly woven and dark in color). Wear wide brim hats. And use eyeglasses that block both UVA and UVB light.

Skin is a very precious and important organ of our body. It has many important functions. It is important for our survival. Let us protect it well – starting from childhood. There is no doubt that melanoma risk rises rapidly with increasing exposure to ultraviolet light in childhood. That’s where prevention should start and then continued into adult life.

Have a great summer!

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Me, Mosquitoes and West Nile Virus

I have been fighting mosquitoes all my life.

I was born and raised on the shores of Lake Victoria. A small town called Musoma, in Tanzania, East Africa. There was no electricity and no telephone. The radio worked on an old fashioned car battery which needed to be charged every couple of days. The drinking water had to be boiled first. And malaria infested mosquitoes were everywhere.

Although much has changed in Africa now, malaria continues to be a dreaded illness. It kills an African child every 30 seconds. Being attacked by mosquitoes was like being attacked by “The Birds” in Hitchcock’s famous movie!

Every evening, all the rooms in the house had to be sprayed with DDT. Each night, at bedtime, we had to take a pill called Paludrin, as a prophylaxis against malaria.

We could not sleep at night without a mosquito net. Quite often a mosquito would get inside the net and buzz all night. You would be lucky if you did not get your blood sucked that night.

Doing home work in the evenings was a nightmare. The kerosene lit lamps would attract all kinds of bugs. The darkness under the table would attract mosquitoes. Malaria infested mosquitoes come out after dark to attack. DDT was used generously.

Then I went to India for higher education. The mosquito problem was the same. Mosquito nets had to be used. But there was no fear of malaria as India was free from that illness.

Then I spent several years in the United Kingdom. I don’t remember fighting mosquitoes there. It was always cold and damp. Mosquitoes are smart. They don’t like cold weather.

In Canada, I did not find mosquitoes a menace until I started golfing. I remember we used to complain about sand flies. Now we talk about mosquitoes only.

I don’t like mosquitoes. I am allergic to their bites. When I go golfing, I apply a good layer of sunscreen. Then I generously spray DEET containing repellents on the exposed areas of my body and some on my clothes.

The chemicals immediately change my body odor. The odor is tolerable when I am on the golf course – my friends probably don’t care how I smell. But when I come home, I am not touchable, not huggable, nor kissable. In spite of a thorough shower, my body odor is chemically compromised for at least 12 to 24 hours

In spite of all the precautions, I still end up getting at least three to five mosquito bites. They itch and burn after a shower. Then I apply After Bite to control the itching. That leaves its own smell on my body. I wonder how much damage these chemicals have caused and continue to cause to my skin and some important organs of my anatomy.

According to World Health Organization website, DDT has now been banned from agricultural use. May be I should have been a vegetable! But DDT still has an important role to play in saving lives and reducing the burden of malaria in some of the world’s poorest countries. Eventually, the plan is to eliminate the production and use of DDT.

Malaria is a life-threatening parasitic disease transmitted by mosquitoes. Today approximately 40 per cent of the world’s population, mostly those living in the world’s poorest countries, is at risk of malaria. It causes more than 300 million acute illnesses and at least one million deaths a year.

Africa is also the source West Nile virus. It was first isolated in 1937 from the blood of a patient on the West Nile province of Uganda. The man had fever. Initially, the outbreaks of the disease were few. But in the last 10 years the numbers have increased.

In North America, the virus was first detected in 1999. It was in New York. From there it was exported to Ontario. Last year, about 400 people in Ontario became infected with the virus. At least 19 people have died.

Most cases of West Nile virus are mild and self-resolving. But one per cent of cases get infection in the nervous system.

As I have learnt over the years, mosquitoes are dangerous. If you want to enjoy the fresh air and the outdoors then learn to protect yourselves. I take no chances. Besides, I react quite badly to the mosquito bites. Ouch!

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Male Breast Enlargement

Enlargement of a male breast (gynecomastia) is not uncommon. Normally, I receive my share of referrals for this condition – approximately two to three cases a year.

Recently, in one month, I saw three patients with gynecomastia. One in early teens, one in late teens and one in his fifties. So I thought it is a good time to review the literature and refresh my knowledge.

Gynecomastia is due to formation of firm tender tissue directly under the nipple. It may affect one breast or both breasts. In pseudo-gynecomastia, enlargement of the male breast occurs due to collection of excessive non-tender fatty tissue. Differentiation is important for investigation and management.

Could it be cancer? Yes, one per cent of all breast cancers are in men.

Gynecomastia can occur temporarily in 60 to 90 per cent of the newborns because of the passage of estrogen (female sex hormone) through the placenta.

Gynecomastia can occur during puberty. This can be anywhere from the age of 10 and peaking between the ages of 13 and 14. Then it declines during the late teenage years.

Gynecomastia can occur in the adult population as well. This occurs usually between the ages of 50 to 80.

At birth, the breast tissues of both sexes appear identical. The tissues remain dormant during childhood. At the time of puberty, the male and female breast tissues start showing features of different development.

In the majority of males, breast changes occur during rapid sexual maturation at the time of puberty. This is followed by reversal of changes and atrophy of breast tissues. But in females, the breast tissues continue to enlarge and develop glands for future production of milk.

Estrogen stimulates breast tissue while androgens (male sex hormones) counteract the effects of estrogen. Gynecomastia is caused by relative imbalance between these two types of hormones.

Sometimes it is difficult to know the exact reason for gynecomastia. It may be associated with other medical conditions. Here is the list:
-25 per cent of gynecomstias are idiopathic (unknown cause)
-25 per cent are due to puberty
-10 to 20 per cent due to drugs (prescription drugs, over-the-counter medicines, illegal drugs)
-8 per cent due to cirrhosis of liver or malnutrition
-3 per cent due to testicular tumors
-2 per cent due to poor testicular function
-1.5 per cent due to over active thyroid
-One per cent due to kidney disease

Breast cancer is very rare in males. It is usually hard, non-tender and can be anywhere in the breast. There may be bloody nipple discharge. There may be dimpling of the skin.

How should we investigate?

All patients need full history (including previous medical problems and use or abuse of medications) and full physical examination (especially examinations of the testicles to see if there is a tumor).

If there is nothing significant to find then most teens do not require extensive blood work because most gynecomastia are part of growing up. A periodic follow-up may be advised. In 90 per cent of teenage boys, gynecomastia goes away in less than 3 years.

Gynecomastia can be due to increased production or decreased breakdown of estrogen, which may indicate a hormonal or liver function work-up (blood tests).

In adults, sometimes the problem can be solved by stopping the medications. Rarely, surgery may be necessary to remove the extra breast tissue.

If a breast enlargement is one sided, hard, and nodular, it is very important to perform a biopsy and mammogram to rule out breast cancer.

If gynecomastia is due to disease or tumor then further treatment is required.

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