health effects of antioxidants

[MrMistery]

I am recently puzzled by the perceived health effects of antioxidants. A lot of people, including science students, seem to still think that antioxidants are in some way required for a healthy life. Does anyone know of any solid research pointing to clear benefits from taking antioxidants? The best I could find is this http://www.ncbi.nlm.nih.gov/pubmed/15153272 people taking antioxidants seem to be just as healthy as people not taking them.

[psionic11]

I'd be very interested in the research and views of the scientific establishment on the benefits of antioxidant-rich foods in the diet. Being informed, but not a scientist, I can only go by what the internet and other mass media hype about antioxidants, and I confess I'm of the belief that there is indeed a benefit. I just had blueberries with my whole wheat and raisin bran cereal, and I have written down lists of the top antioxidant-rich foods, making conscious decisions on what to eat based on those lists.

blueberries
beans of all kinds
oregano
vitamin C in fruits and veggies
beta-carotene in carrots, beets, yams
broccoli
red wine
apples
walnuts
athletic drinks fortified with antioxidants

Am I victim of a marketing scam? Of course, I indulge in the occasional beer or burger and fries, but by and large I try to include more veggies than fat, more meat than starch, and more nutritional value than the sugar/complex carb/fatty/salty based "feel-good" foods that's making the American animal obese beyond belief. And that includes sugary, "feel-good" mass media like TV and pop radio that also makes Americans mentally obese.

Sorry, I digressed there. All I can contribute factually is this:

Red Wine Compound Resveratrol Demonstrates Significant Health Benefits
Broccoli May Help Protect Against Respiratory Conditions Like Asthma
Antioxidant Deficiency Linked To Pulmonary Hypertension
Dry Beans Inhibit Development Of Mammary Cancer

Then again, there's this for the opposing view:

Vitamins C And E And Beta Carotene Again Fail To Reduce Cancer Risk In Randomized Controlled Trial

Unless the lay person like me has access to "harder" science publications like PubMed....? (Oops, wait a minute, I just discovered that I can make searches from the PubMed link. Woot! Thanks, MrMistery).

Perhaps it's not so much that antioxidants have proactive preventive effects against chronic diseases, but moreso that a lack of antioxidants tends to precipitate conditions ripe for chronic ailments...

[wolfhnd]

Seems that oxidants also have health benifits

viewtopic.php?f=108&t=12780

obviously this is a very complex problem.

[MrMistery]

There are documented health effects of eating vegetables and fruits, but the effects may not be due to the antioxidants.
And there are studies saying that for some things antioxidants may be bad for you http://www.pnas.org/content/106/21/8665.full Let's not forget the body developed its own antioxidant, gluthatione, to handle reactive oxygen.

Oh, and just as a fun fact: the biggest source of antioxidants in the average person's diet is coffee. Just because something is addictive doesn't mean it is bad for you

[BioWizard]

The body uses oxidants which it produces to mediate very important functions such as control of blood flow and immune function. Too much antioxidants is actually a bad thing and can interfer with a healthy balance. The reason fruits and veggies are so hyped in the west is because people eat too much processed food that is poor in nuitrition and vitamins. Also, the high fat high protein diet produces a lot of acidic metabolites which strains the body while trying to maintain normal pH (all other health risks notwithstanding).

So eat your vegetables and fruits, enjoy your steak, have a beer or a glass of wine with your dinner, ts'all good.

[Bill Davis]

Grandma's outlook: Have some of everything and not too much of anything, that is the best thing.

Odd how we end up back at this time and time again.

[anne12]

Hello Friends...........

1.Antioxidants can cancel out the cell-damaging effects of free radicals. and there is evidence that some types of vegetables, and fruits in general, protect against a number of cancers. These observations suggested the idea that antioxidants might help prevent these conditions.

2.antioxidants are commonly used as medications to treat various forms of brain injury.

Thanks

[neuro]

four rapid notes:
- as long as cells function ok, they can manage the free radicals (ROS, reactive oxygen species) they produce as a consequence of cellular respiration, with no harm
- particularly unbalanced diets can put cells in such a condition that they may overproduce ROS (this occurs for example in diabetes) od have problems in handling them
- in the presence of pathological cellular biochemical defects (in particular neuronal, e.g. Parkinson's disease, Alzheimer disease, ALS), ROS may precipitate cellular oxydative stress and cell death
- exogenous antioxydants may help under the conditions above, but they are not particularly effective as almost none of them are able to get to significant extent to mitochondria (within cells) which is the site they should act at

[Sunne]

"Green tea contains high concentrations of catechin polyphenols. These compounds work in the body with other chemicals to heighten levels of fat oxidation and thermogenesis (a state created in the body by burning fat as fuel). On average, you should try to consume a minimum of three cups of green tea per day for weight loss effects. Green tea has also been shown to be preventative against cancer, heart disease and high cholesterol."

http://www.canadianliving.com/health/nu ... ting_2.php

[Aldrich]

Hey buddy in my opinion I think that no one can take any kind of the medication with out any doctor's prescription.... Because we don't know the efficacy and the salt inside them and the dosage of the medicine's also.... So be careful while taking any kind of the medicine ......

[henryfayols]

Without checking the pkg. & expiry dates no one should take the medicine.It should not be taken unnecessarily.It will have adverse effects to the body.The person can suffer from paralyses,B.P,etc..So, they should not take it without the advise of the doctor.

[Bothom]

Antioxidants helps you to decrease your hunger. you can say that it is anabolic effect.
It is present in green tea and wheat grass.

[BioWizard]

Antioxidants helps you to decrease your hunger. you can say that it is anabolic effect.
It is present in green tea and wheat grass.

How is decreasing your hunger an anabolic effect? And how do antioxidants reduce hunger anyway?

[neuro]

I should not like to discourage the hopes of anybody, but there is no experimental clue whatsoever that anti-oxidants should make you lose weight...

Just to be clear and simple, anti-oxidants are marvellous substances that - too bad - do not produce any desirable effects other than protecting the cells from their own (inevitable) production of reactive oxygen species, during cellular respiration.

A further problem is that, in order to be truly effective, anti-oxidants should need to enter mitochondria, which they generally don't.

Still, a mild protective effect has often been reported, and may justify their use in a series of pathologies characterized by liability to oxidative stress on the part of specific cellular populations.

[BioWizard]

A further problem is that, in order to be truly effective, anti-oxidants should need to enter mitochondria, which they generally don't.

I never thought of it that way. Is it strictly true? Don't a lot of the cell's native antioxidants work in the cytosol? There's the cytoplasmic version of superoxide dismutase, and also glutathione reductase, and the various antioxidant vitamins which work somewhere around the cytoplasm. I always thought it was the ROS that escapes mitochondria that does most of the damage (around various compartments in the cell, not just the mitoplasts).

[neuro]

I always thought it was the ROS that escapes mitochondria that does most of the damage (around various compartments in the cell, not just the mitoplasts).

I agree. You are right, and I was too drastic in my previous post.

Still, the normal cellular endowment of enzymes and cofactors to neutralize ROS is largely sufficient to protect the cell from damage, provided not too many ROS escape mitochondria (or too many are produced, which appears to me as the crucial point)

[BioWizard]

I always thought it was the ROS that escapes mitochondria that does most of the damage (around various compartments in the cell, not just the mitoplasts).

I agree. You are right, and I was too drastic in my previous post.

Still, the normal cellular endowment of enzymes and cofactors to neutralize ROS is largely sufficient to protect the cell from damage, provided not too many ROS escape mitochondria (or too many are produced, which appears to me as the crucial point)

Ok, I see where you're coming from. I've always held that antioxidants can't significantly affect the ageing of an organism, unless the organism has some intrinsic disorder that affects it's native oxidant/antioxidant functions (and research supports that notion). They can, however, keep tissue in a relatively healthier state if the tissue is under constant stress.

[jodieB]

Nice article. thanks for the post. It seems that oxidants also have its health benefits.

[psionic11]

It's hard to separate the science media from the science fact. Neuro, I understand that (organic sources of) antioxidants may not be able to reach the cell nuclei due to the cell membrane barriers, but there must be some reason for all the literature on the supposed beneficial effects of AOX-rich foods....

Perhaps they do their most beneficial work beyond the normal mitochondrial reach... say at the outside membrane layers and at the other majority sources of intracellular reactions outside cell walls?... Maybe in concert with the glandular secretions and other hormones that travel throughout the body's systems?

Or am I mistaken in assuming that glandular secretions generally don't permeate individual cell walls but do most of their work at a systemic level?

[neuro]

psionic11,
you are right.
As pointed out by Biowiz, antioxidants act in the cytosol as well, and here is where reactive oxygen species (ROS) produce their big damages.

My point only is that in general exogenous antioxidants are not NEEDED in the cytosol, unless ROS are produced in large excess in mitochondria

[Lomax]

Incidentally, there was an article in Slate about this today, and another last year. Most notably: the meta-analysis by Bjelakovic et al finds that antioxidant supplementation increases mortality rate.

[psionic11]

Oi vey, anti-oxidant supplements are bad for you. I can't past much of the medical jargon, but I'm going to assume that the key word is "supplement". A diet that happens to be high in naturally occurring antioxidants -- beans, blueberries, nuts, broccoli, spinach, fish -- won't send you to the grave earlier, but taking supplements will, correct?

I guess I should ease up then on my two daily supplements of a multivitamin and melatonin before bedtime... sigh...

[bryaninbry]

cf Nick Lane in 'Oxygen - the Molecule that made the World': he quotes the authors Halliwell and Gutteridge, authors of " Free Radicals in Biology and Medicine" as saying "by the 1990s it was clear that antioxidants are not a panacea for ageing and disease, and that only fringe medicine still peddles this notion"

No reason not to eat your 5 fruit and veg a day, though! Vit C and fibre still essential - but all the dozens of bits and bobs in vitaminn pills are pretty irrelevant if you have a decent diet.

[Lomax]

Oi vey, anti-oxidant supplements are bad for you. I can't past much of the medical jargon, but I'm going to assume that the key word is "supplement". A diet that happens to be high in naturally occurring antioxidants -- beans, blueberries, nuts, broccoli, spinach, fish -- won't send you to the grave earlier, but taking supplements will, correct?

Well... at least half-correct. I mean, the study doesn't compare supplemented antioxidants to natural antioxidants, so the effects of natural ingestion are unclear. At least some scientists think that the mortality risk lies with antioxidation, not supplementation.

[neuro]

It should be noted that antioxidants are not substances that push a specific cellular biochemical reaction in a specific direction.

In general, the direction a biochemical reaction proceeds in a cell is determined by the complex of other related reactions (i.e. if products are subtracted the reaction proceeds forwards, if products are there and the reagents are subtracted by other reactions, then the reaction proceeds backwards).

Catalysts and enzymes only accelerate reactions (i.e. they do not determine the direction), apart from enzymes which couple a specific reaction with energy release by ATP, or similar, in which case they do determine the direction of the reaction, because the energy released by ATP is sufficient to unbalance the coupled reaction and push it uphill (thermodynamically speaking).

Anti-oxidants in general are cofactors, i.e. they are molecules that can host a single (unpaired) electron without becoming aggressive/reactive, which makes it possible to detoxify compounds that instead are very reactive (and toxic) when they carry an unpaired electron (e.g. hydroxy radicals, superoxide ion, nitric oxyde and other ROS), because they oxidize membrane lipids and cellular proteins (subtract them another electron to pair their own single unhappy one) and impair their functioning. This means antioxidants are not ANTI-oxidant, strictly speaking, but they simply make it easier for the cell to dispose of dangerous unpaired electrons (and "oxidants").

So, the simple question is that a cell which does not have a sufficient "buffer" for unpaired electrons (antioxidant reserve) is prone to oxidation by ROS and subsequent damage; in principle, it can profit of exogenous antioxidants. A cell which does possess the adequate amount of antioxidant cofactors may still suffer oxidative damage if cell respiration is pushed to hard (e.g. in diabetes, due to excess "fuel"); in principle, in this case as well antioxidant may be useful. Otherwise, loading a cell with antioxidant may only interfere with its own regulation of oxidative potential and in general - more or less specifically - with many other biochemical reactions; which may result in more damage than benefit.

This actually is a general rule (e.g. it is the same for vitamins): we usually heal notwithstanding doctors and cells usually know of their business, they can get what they need and disregard what they don't. If no pathological alterations of cellular processes are present, loading cells with anything, in a non-physiological way, will certainly produce mora harm than help.

[Danny]

Hi, Supplements is good for health or Harmful ?
I think Supplements is not good for human health its have some side effects...
what you think about this??

[neuro]

The most important aspect is that your diet be varied and balanced.

In such case, the organism is well conceived to use what it needs and dispose of the rest.

In case of a diet which is not sufficiently varied and balanced, essential aminoacids, vitamins, oligo-elements and other necessary nutrients might be inadequately assumed. In such cases supplements are useful.

It is not like enhancing the octane power of fuel, to increase the power of the motor of your car: your motor/body already is studied to work at best, provided you give it what it needs - you cannot push it to work "better" giving it MORE of what it needs...

[jrdn86]

Quite an eye-opener for antioxidants. Personally, I've never heard of reports that antioxidants are bad for the human body so this is definitely a first for me. It's also quite surprising since there are massive antioxidants that are competing in the market. I've seen quite a lot and it surprises me that none has ever made a complaint in taking those. If you ask me, drinking water is the best way to get antioxidants inside your body.

[nofools]

In my Biochemistry textbook, it is stated that though natural antioxidants are extremely beneficial to human body, but taking them from external sources doesn't replicate the benefits. One possible reason for this is that these antioxidants act only in the presence of other substances in specific proportions. Unfortunately, we do not yet know about those substances and their compositions.

[wunderkind]

interesting that nobody mentioned vitamin C , which is a very good anti-oxidant

I take 4-6 grams a day , buffered with calcium

ascorbic acid