What is the clinical relevance of vitamin C in lead-exposed infertile men? Compared to controls, lead-acid battery workers who were given 1,000 mg of vitamin C daily for three months experienced “a significant increase in sperm motility and sperm count, and a decrease in abnormal sperm” and “a significant decrease in sperm incidence” DNA fragmentation, “ie damaged sperm DNA. Okay, but the ideal ending point would be boys and girls hopping. Take part in this extraordinary little study from the University of Texas more than 30 years ago.
27 men with fertile women had tried unsuccessfully to have children for years. Twenty of them received 1,000 mg of vitamin C per day for two months, and seven acted as controls, not receiving vitamin C. The researchers followed up at the end of the 60 days. By then, every single woman for each of the 20 men who received the vitamin C had become pregnant – 20 out of 20! After years of frustration boom: 100 percent pregnant. In addition, not a single woman of the men in the control group became pregnant. Such black and white results are rarely seen in the medical literature for an intervention.
Does vitamin C reduce the oxidative stress of lead or does it actually lower the lead content? Sure, antioxidant supplementation can have antioxidant effects, but it may not actually lower blood lead levels. This happened in a group of workers who breathed lead day in and day out, and the way vitamin C can work is by simply blocking the “intestinal absorption of lead”. A previous study showed that vitamin C supplementation apparently reduced lead levels by a third within six months, but with a whopping 2g dose with added zinc. Another small study found the same 30 percent decrease with just 500 mg a day, without zinc, and in just one month. But none of these studies had a control group of subjects who took nothing, so we don’t know if their levels would have dropped anyway.
Similarly, there is an almost too good study to be true of the role of vitamin C in eliminating lead toxicity from “biosystems”, by which they mean children. They received 250 to 500 mg of vitamin C per day for a few months, and shaved hair samples dropped lead levels by up to 69 percent each month. The researchers repeated it in two other small groups of children and saw the same amazing drops in each and every child. But maybe lead levels have dropped across the community during this time? Without measuring lead levels in a control group of children who are not taking vitamin C, we cannot be sure.
As I illustrate from 3:17 in my video Yellow peppers for male infertility and lead poisoning?At eight weeks of vitamin C, the lead content in the blood decreased and increased in the urine. One might infer that the vitamin C was pulling lead out of the body, but the same thing happened in the placebo group: blood levels fell and urine levels rose. So it had nothing to do with vitamin C at all. That is why it is always important to have a control group.
The same applies to studies that apparently showed no benefit. For example, 36 workers in battery manufacturing were examined. Everyone received vitamin C, but there was no change in lead levels. But perhaps their coworkers saw a large spike in lead over the same period, and the vitamin C actually succeeded in preventing the subjects’ lead from rising. You don’t know without a control group.
This is why studies such as “The Effects of Vitamin C Supplementation on Cadmium, Lead and Mercury Levels in Blood and Hair” are so important. Vitamin C compared to a placebo with an identical sugar pill. The result? The vitamin C didn’t help, which really dampened the craze for using vitamin C for lead poisoning until a now-well-known study was published in 1999 that showed that vitamin C supplementation can lower blood levels. As you can see in my video at 4:32 a.m., after four weeks of taking a placebo in the control group, there wasn’t a huge change in blood lead levels, which we would expect. In contrast, the vitamin C group began with roughly the same blood lead levels as the control group, but within a week of taking 1,000 mg of vitamin C per day, lead levels decreased 81 percent. Therefore, supplementing with vitamin C “may be an economical and convenient way to lower the level of lead in the blood, possibly by reducing the intestinal absorption of lead.”
The levels of lead in the urine have not changed, so it is not as if the subjects excreted more lead in their urine to lower their blood levels. Most of the lead in our blood, however, is in the red blood cells, which are recycled in the liver and passed into the intestines via the bile, where the lead can easily be reabsorbed – unless you may be high in vitamin C. in to block absorption. But 1,000 mg is a lot of vitamin C. Would about 200 mg, which is roughly the amount of vitamin C you get in an orange and a cup of broccoli or strawberries, work? The researchers also tested that. The 200 mg group started off the same as the control and 1000 mg groups, but the blood lead levels didn’t really move. Pity! So 1,000 mg seemed to work, but 200 mg didn’t. Isn’t 1,000 mg of vitamin C a little unnatural? The recommended daily dose is only 60 mg. In fact, we may have moved on for millions of years and got closer to 600 mg per day – ten times the current recommended daily allowance – because we have eaten so many fruits and vegetables. Okay, but could you get 1,000 mg of vitamin C without taking pills? Yes! This is, for example, the amount of vitamin C contained in three yellow peppers.
Other videos in my series on lead are:
- Is lipstick safe in the face of lead contamination?
- Can saunas detoxify lead from the body?
- How the lead paint industry got away with it
- Lead in drinking water
- How the leading gas industry got away with it
- “Normal” blood lead levels can be toxic
- The effects of low lead exposure in adults
- How to lower lead levels with diet: thiamine, fiber, iron, fat, fasting?
- How to lower lead levels with diet: breakfast, whole grains, milk, tofu?
- Best foods for lead poisoning: chlorella, coriander, tomatoes, moringa?
- Best food for lead poisoning: garlic
- Can Vitamin C Help With Lead Poisoning?
- How much lead does organic chicken soup (bone broth) contain?
- Lead in calcium supplements
- Should Pregnant Women Take Calcium Supplements to Lower Lead Levels?
- The rise in blood lead levels during pregnancy and menopause
- Lead contamination in fish and game
- Lead contamination in hot sauces
Note that yellow peppers are nothing special – other than their exceptional vitamin C content. I’ve only used them as a convenient way to get 1,000 mg of whole-food vitamin C. They are certainly easier than eating ten oranges!
But remember my video Bell Peppers And Parkinson’s: The Benefits Of Smoking Without Risks? So one would expect to get all of the benefits of 1,000 mg of vitamin C with benefits. Why not just take vitamin C supplements? See Do vitamin C supplements prevent colds but cause kidney stones?
If hundreds of milligrams of vitamin C per day sound like a lot, take a look at this What is the optimal vitamin C intake?
You may be interested in my Vitamin C and Cancer series:
For more information on male fertility, see:
Michael Greger, MD
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