What's The Harm?

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What's The Harm?

Postby JeffN » Wed Apr 16, 2008 6:44 am

One of the most common responses you hear from supplement users, is that even if there is not any benefit, what is the harm in using them. Maybe they just offer come extra insurance, and/or protection.

Apparently not. And, this is not the first study to show this.

But, this one just came out from the Cochrance Group, which is one of the most respected groups out there for reviewing medical research.

In Health
Jeff

Vitamins 'may shorten your life'

Research has suggested vitamin supplements do not extend life and could even lead to a premature death.

A review of 67 studies found "no convincing evidence" that antioxidant supplements cut the risk of dying.

Scientists at Copenhagen University said vitamins A and E could interfere with the body's natural defences.

"Even more, beta-carotene, vitamin A, and vitamin E seem to increase mortality," according to the review by the respected Cochrane Collaboration.

The research involved selecting various studies from 817 on beta-carotene, vitamin A, vitamin C, vitamin E, and selenium which the team felt were the most likely to fairly reflect the benefits of the supplements.

It has been thought that these supplements may be able to prevent damage to the body's tissues called "oxidative stress" by eliminating the molecules called "free radicals" which are said to cause it.

This damage has been implicated in several major diseases including cancer and heart disease.

'Just eat well'

The trials involved 233,000 people who were either sick or were healthy and taking supplements for disease prevention.

After various factors were taken into account and a further 20 studies excluded, the researchers linked vitamin A supplements to a 16% increased risk of dying, beta-carotene to a 7% increased risk and vitamin E to a 4% increased risk.

Vitamin C did not appear to have any effect one way or the other, and the team said more work was needed into this supplement - as well as into selenium.

In conclusion, "we found no evidence to support antioxidant supplements for primary or secondary prevention," they said.

It was unclear exactly why the supplements could have this effect, but the team speculated that they could interfere with how the body works: beta-carotene, for instance, is thought to change the way a body uses fats.

The Department of Health said people should try to get the vitamins they need from their diet, and avoid taking large doses of supplements - a market which is worth over £330m in the UK.

"There is a need to exercise caution in the use of high doses of purified supplements of vitamins, including antioxidant vitamins, and minerals," a spokesperson said.

"Their impact on long-term health may not have been fully established and they cannot be assumed to be without risk."
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Postby Quiet Heather » Wed Apr 16, 2008 9:12 am

Did they only look at vitamin A in the form of beta carotene or did they also look at other vitamin A sources?

What is your opinion on prenatal vitamins?
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Postby momof4 » Wed Apr 16, 2008 9:37 am

This subject was talked about briefly last night in my CHIP class. On the video, someone asked about supplements--the RD said that eating real, whole foods is the best way to go. She said in a glass of orange juice, there are over 500 phytochemicals, and there's no way that any supplement comes close to that. There is such a complexity of nutrients in food, there's still a lot we don't know about, and so supplements are missing some--she said she has a fear of creating an imbalance if she takes them. She said there are exceptions if someone has a medical issue that requires supplementation, but for the majority of people, they were unnecessary and perhaps harmful.
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Colin Cambell adresses this

Postby SactoBob » Wed Apr 16, 2008 10:09 am

I am not sure if it was in his book, lecture, or audio interviews, but Campbell believes that most supplements are harmful. His theory is that there are many chemicals in our foods which work in ways we don't understand.

Our bodies are designed to handle nutrients which are packaged in whole plant foods in the proportions found in the foods. By altering the proportions by emphasizing a single nutrient (supplement), we upset that balance.
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Postby Jaggu » Wed Apr 16, 2008 11:16 am

Any word on B12 supplements for long term vegetarians that's been approved by Dr McD, Dr Jeff and Dr Essylstene?
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B12 is the exception

Postby SactoBob » Wed Apr 16, 2008 12:23 pm

I am not aware of any controversy on this. Everybody seems to agree that for long term vegans, a B12 supplement is a good idea. Even Dr. Campbell takes one (because his wife makes him, he says).
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Postby JeffN » Wed Apr 16, 2008 1:33 pm

Quiet Heather wrote:Did they only look at vitamin A in the form of beta carotene or did they also look at other vitamin A sources?


Both Vit A and beta carotene have been shown to be harmful in studies.

Quiet Heather wrote:What is your opinion on prenatal vitamins?


The same. :)

My recommendation is to eat as healthy a diet as you can. Then, if you would like, you can analyze it to see how well you are doing.

If you find some potential areas that may be low, then adjust the food you eat to cover these areas.

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Postby Jaggu » Wed Apr 16, 2008 1:47 pm

Jaggu wrote:Any word on B12 supplements for long term vegetarians that's been approved by Dr McD, Dr Jeff and Dr Essylstene?


Jeff,

This seems to have missed you radar screen :-)

Scatobob, thanks, I just want to make sure that that is the case.
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Postby Quiet Heather » Wed Apr 16, 2008 1:48 pm

Thanks, Jeff. That's what I thought. :)
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Postby JeffN » Wed Apr 16, 2008 1:57 pm

Jaggu wrote:
Jaggu wrote:Any word on B12 supplements for long term vegetarians that's been approved by Dr McD, Dr Jeff and Dr Essylstene?


Jeff,

This seems to have missed you radar screen :-)

Scatobob, thanks, I just want to make sure that that is the case.


Sactobob is right on 100%.

You can read my recommendations here..

http://www.drmcdougall.com/forums/viewtopic.php?t=5844

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What is a "large dose"?

Postby Burgess » Wed Apr 16, 2008 7:12 pm

The quoted report (or report of a report) says: "...avoid taking large doses of supplements ...."

What constitutes "large"?

Because my diet is more limited than the regular McDougall diet, I take--every four days--a standard one-a-day tablet of vitamins and minerals, mostly at 100% of recommended daily allowance, but with 25 micrograms of B12 in each tablet.

My assumption is that I am getting the B12 I need (average of 6 micrograms per day) plus a low dose (1/4 of RDA per day, average) of everything else.
Burgess Laughlin, Star McDougaller
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Re: What is a "large dose"?

Postby JeffN » Wed Apr 16, 2008 7:49 pm

Burgess wrote:The quoted report (or report of a report) says: "...avoid taking large doses of supplements ...."

What constitutes "large"?

Because my diet is more limited than the regular McDougall diet, I take--every four days--a standard one-a-day tablet of vitamins and minerals, mostly at 100% of recommended daily allowance, but with 25 micrograms of B12 in each tablet.

My assumption is that I am getting the B12 I need (average of 6 micrograms per day) plus a low dose (1/4 of RDA per day, average) of everything else.


Good question.

While this was a "meta-analysis" and looked at many studies using different amounts, most of these amounts are over what you would find in a general multi vitamin and mineral tablet.

I would be much less concerned with someone getting in 1/4 the RDA then someone taking megadoses.

If you have never done the experiment, you might want to input a weeks worth of food into a nutritional analysis program (like CRON-O-Meter) and see how much you are really getting in.

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Re: What is a "large dose"?

Postby Burgess » Wed Apr 16, 2008 9:36 pm

JeffN wrote:If you have never done the experiment, you might want to input a weeks worth of food into a nutritional analysis program (like CRON-O-Meter) and see how much you are really getting in.

As an ideal, I specified 15% of calories from protein, 8% from fat, and the rest from carbohydrates. I am 72 inches tall, and weigh 135 pounds.

Here is the summary I got from typing in part of one meal. (The meal is not complete; it does not include the 1/2 c of dried fruit, the T of canola oil, or the sugar that is part of the pumpkin/hazelnut dessert I eat at almost every meal.)

This is all very rough. I won't swear by the details, especially quantities, that I typed in, but the amounts are roughly correct. I may have overestimated the amount of potatoes.

I have simplified the food descriptions below. I eat a lot of food (about six cups per meal).
units, serving size, calories
Pumpkin, canned 1, cup, 83.3
Potatoes, Russet, baked 2 potato medium (2-1/4") 335.6
Sweet potato, bkd 1 medium 102.6
Hazelnuts 1, 10 nuts, 87.9
Vegetables, mixed 2, 1/2 cup, 109.2
Honey 2, tbsp, 125
Grapefruit, raw 2, 1/2 fruit (3-3/4" dia), 77.9

Here is the summary I got for the one meal:

actual/daily projected
Calories 988/2452 40% (of daily target, apparently)
Protein 23g/56 g 41%
Carbs 215g/130 g 160%
Lipids 10g/65g 16% ???
Vitamins 61%
Minerals 68%

In the list of minerals, I was under in calcium (22%) and selenium (14%).
I suspect the standard calcium recommendation is inflated. I don't know about selenium. (I recall reading on labels that the selenium recommended level had not been set.)

Generally I can see that I am getting plenty of nutrition!

I see only three potential problems:
1. Lipids--but I don't know what they are. (A kind fat?)
2. Selenium.
3. B12 (but I already knew about this, hence my supplement)

My reference, The Wellness Encyclopedia of Food and Nutrition, says a strong plant source of selenium is garlic, which I consume in quantities of about 1 T per day, but I didn't include it in the calculations. (All other sources are animal products or grains, which I don't eat.)
Burgess Laughlin, Star McDougaller
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My health weblog: http://anti-itisdiet.blogspot.com
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Re: What is a "large dose"?

Postby JeffN » Thu Apr 17, 2008 8:00 am

Burgess wrote: This is all very rough.


They I will respond "roughly". :)

Burgess wrote:In the list of minerals, I was under in calcium (22%) and selenium (14%). I suspect the standard calcium recommendation is inflated. I don't know about selenium.


You can set the requirements yourself in the program. It is true that our calcium goals are overinflated in this country. Even the NAS and WHO and Harvard, acknowledge that if we reduced our sodium levels and our animal protein intake, and got in adequate Vit D and Vit K, our true need is somewhere around 500-750. ANd, there are many areas that do well on levels of 300-500 with little osteoporosis or bone fractures.

Selenium is set at 55 mcs for an adult male. That is probably fairly adequate and was actually "lowered" from 70 at the last revision.

Burgess wrote:
I see only three potential problems:
1. Lipids--but I don't know what they are. (A kind fat?)
2. Selenium.
3. B12 (but I already knew about this, hence my supplement)


In regard to lipids, these are "fats." It is interesting to look at them, but you only need to set omega 3s at 1.1 to 2.2 at most. Then set Omega 6 at nor more than 4x the Omega 3s.

In addition, you can set saturated fat at 5-7% of calories. So, if you figure you eat 1800 calories is 10- 14 grams max of saturate fat.

Selenium and B12 we covered.

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Postby JeffN » Thu Apr 17, 2008 9:21 am

From the NAS

Note: Keshan disease is one of the main concerns of low selenium. EAR = Estimated Average Requirement

"Surveys in China have compared per capita daily selenium intakes of adults in Keshan disease areas with intakes in adjacent areas that were free of the disease (Yang and Xia, 1995; Yang et al., 1987). Adult subjects living in the affected areas were found to have selenium intakes of 11 µg (0.14 µmol)/day or less, while those living in unaffected areas had intakes of 17 µg (0.22 µmol)/day or more. Thus, based on one Chinese study, no selenium-responsive disease is known to occur in populations with adult intakes as low as 17 µg (0.22 µmol)/day.

Additional results from China and elsewhere indicate that intakes of 20 µg (0.25 µmol)/day and greater protect adults against the development of Keshan disease (Yang et al., 1987). In New Zealand and Finland, intakes by adults as low as 25 µg (0.32 µmol)/day have been reported without the occurrence of Keshan disease (Griffiths, 1973; Varo et al., 1994)."

Also..

Based on the criterion of maximizing plasma glutathione peroxidase activity, the data described above support a selenium EAR of 45 µg/day for the age group 19 through 50 years based on the weights of North American men. Given the reported greater susceptibility of women to develop Keshan disease and the fact that the data used to set the EAR came largely from men, selenium requirements for both males and females are based on the higher reference weights for males.

The RDA for selenium is set by assuming a coefficient of variation (CV) of 10 percent (see Chapter 1) because information is not available on the standard deviation of the requirement for selenium; the RDA is defined as equal to the EAR plus twice the CV to cover the needs of 97 to 98 percent of the individuals in the group there fore, for selenium the RDA is 120 percent of the EAR). The calculated RDA is rounded to the nearest 5 µg.

From the FAO

" Starting at frankly deficient levels, total daily selenium intakes of above 41 µg/day were found sufficient to increase plasma GSHPx substantially and to saturate plasma activity in 60-kg male subjects within 5-8 months. It was estimated that satisfactory levels of plasma selenium (>80 µmol/l) and of GSHPx (>0.3 mmol NADPH oxidized/min/l; approximately two-thirds of plasma saturation activity) indicative of adequate selenium reserves would be attained after intakes of approximately 27 µg/day by 65-kg male subjects (86). Such criteria satisfying the definition of average normative requirements for selenium () have been used as the basis for calculating recommended nutrient intake (RNI) values in this report after interpolating estimates of average requirements by allowing for differences in weight and basal metabolic rate of age groups to up to 65 years and adding a 25 percent increase (2 x assumed SD) to allow for individual variability in the estimates of RNI (Table 52).

As a result the FAO's Recommended nutrient intake sets the level for adult males at 34. (27 x 1.25=33.75, rounded up to 34)

So, it seems a level of 17 to 25 may be closer to what a true "minimum" level is and 27 to 34 may be more of a "adequate intake", where is the 55 is the safer number recommended to the general population"

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