Yellow Bell Peppers for Male Infertility & Lead Poisoning?

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What is the “[c]linical relevance of vitamin C among lead-exposed infertile men”? Compared to controls, lead battery industry workers given 1,000mg of vitamin C every workday for three months experienced “a significant increase in sperm motility and sperm count, as well as a decrease in abnormal sperm,” as well as “a significant reduction in the incidence” of damaged DNA. Okay, but the ideal endpoint would be bouncing baby boys and girls. Enter this extraordinary little study from the University of Texas from over 30 years ago.

Twenty-seven men with fertile wives, yet trying to have kids for years, to no avail. Twenty of them were given 1,000mg of vitamin C a day for two months, and 7 acted as controls: no vitamin C. They followed up at the end of the 60 days, and by then every single one of the 20 women became pregnant—20 out of 20! Years of frustration, and then boom: 100% pregnant, and not a single one of the women in the control group got pregnant. Rarely does one see these kind of black-and-white results in the medical literature for any intervention.

Is the vitamin C just lowering the oxidative stress from the lead, or actually lowering the level of lead? Sure, antioxidant supplementation can have antioxidant effects, but may fail to actually lower lead levels in the blood. Now, this was in a group of lead workers that were breathing the stuff day in and day out, and the way vitamin C may work is to just block the “intestinal absorption of lead.” An earlier study showed C supplementation apparently cut lead levels by a third within six months—but that was with a whopping two-gram dose, with added zinc. Another small study found the same 30% drop with just 500mg a day; no zinc—and, in only one month. But neither of these studies had a control group that didn’t take anything. So, you don’t know if maybe their levels would have fallen anyway.

It’s like this almost too-good-to-be-true study on the “[r]ole of [vitamin C] in scavenging…lead toxicity from biosystems”—by which they meant children. 250 to 500mg a day of vitamin C for a few months, shaving hair samples every month, and saw up to a 69% decline in lead levels. So, they repeated it in two other small groups of kids, and saw the same amazing kind of drops in every single child. But, maybe lead levels were just dropping throughout the whole community during that time? Without measuring lead levels in a control group of kids not taking vitamin C, we can’t be sure.

Here’s a good study to illustrate. Eight weeks of vitamin C and lead levels dropped in the blood, and rose in the urine. One could conclude that the vitamin C was like pulling lead out of the body, but the same things happened in the placebo group: blood levels dropped, and urine levels rose. So, it had nothing to do with the vitamin C at all. That’s why it’s always important to have a control group.

The same with studies that appeared to show no benefit. 36 battery workers, all given vitamin C; no change in their lead levels. But maybe their co-workers during that same time period suffered a huge increase in lead levels, and the vitamin C was actually successful in keeping levels from rising. You don’t know without a control group.

That’s why studies like this are so important: “Vitamin C or placebo.” Vitamin C versus an identical-looking sugar pill, and the vitamin C failed to help. That really put a damper on enthusiasm for using vitamin C for lead poisoning—until this now-famous study was published in 1999, which showed that vitamin C supplementation could lead to a decrease in blood levels. But, check this out. Here’s where the control group started, and after four weeks of taking a placebo, pretty much nothing happened, which is what you’d expect. Okay, but check out the vitamin C group. Started out at about the same, but within one week of taking 1,000mg of vitamin C a day, lead levels dropped 81%. So, “[vitamin C] supplementation may provide an economical and convenient method of reducing blood-lead levels, possibly by reducing the intestinal absorption of lead.”

See, the urine lead levels didn’t change; so, it’s not like they were peeing out more lead to bring down their blood levels. But, most of the lead in our blood is in the red blood cells, which are recycled in the liver, and discharged through the bile into the gut where the lead could just get reabsorbed—unless, perhaps, you’ve got a lot of vitamin C in there to block the re-absorption. But 1,000mg is a lot of vitamin C. Would something like 200mg work, which is just like an orange and a cup of broccoli or strawberries? They tested that, too! The 200mg group started out about the same, and didn’t really budge. Bummer! So, 1,000 seemed to work, but 200 didn’t. Isn’t 1,000 a bit unnatural, though? I mean the RDA is only 60.

Well, actually, we may have evolved for millions of years getting closer to 600mg a day: ten times the current RDA, because we were shoveling in so many fruits and greens. Yeah, but could you reach 1,000mg without having to take pills? Sure! That’s the amount of vitamin C, for example, that can be found in three bell peppers.

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Icons created by Jamison Wieser from the Noun Project.

Image credit: milanmarkovic via 123RF. Image has been modified.

Motion graphics by Avocado Video. 

• antioxidants
• bell peppers
• broccoli
• children
• DNA damage
• fertility
• fruit
• greens
• heavy metals
• infertility
• lead
• men's health
• oranges
• pregnancy
• sperm counts
• strawberries
• supplements
• vegetables
• vitamin C
• zinc