vegetable fats vs fish oil

[Guest guest]

Here is an article from www.mercola.com I get his newsletter in my e-mail

and it often has interesting health info. This information, is similar to

the information about the dangers of vegetable oils in the " Well Being

Journal " (Vol 14, no. 3....may/june 2005) magazine that I bought at our

local healthfood co-op a couple of weeks ago. I hope this is of interest to

some.

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Age-related cataract, a cataract that occurs in the elderly and is

characterized by an initial opacity in the lens, is an extremely common

disorder that has both substantial health and economic effects. In fact,

age-related cataract is the leading cause of blindness in the world.

Although the visual impairment associated with cataract can be corrected

surgically, it is at a major social cost, as cataract removal is the most

frequently performed surgical procedure among Medicare patients, costing

some $3.5 billion a year in the United States.

This study examined the association between specific types of fat in the

diet, measured over a period of 10 to 15 years, and the development of

cataracts. This is the first published study to perform this extensive type

of dietary analysis with cataracts.

Polyunsaturated fats (PUFAs) are essential fats and consist of omega-6 and

omeg-3 fats. PUFAs have generally been considered to be healthy elements of

the diet. Linoleic acid is an 18-carbon omega -- 6 PUFA. It is abundant in

the Western diet and is the major fatty acid in safflower, sunflower, corn,

soybean and cottonseed oils, as it accounts for more than 50 percent of the

total fatty acid content in these oils. Although linoleic acid is an

essential fatty acid, the consumption of modest amounts, equivalent to 1

percent of total calories, is adequate to protect against essential fatty

acid deficiency.

Linoleic acid constitutes up to 0.5 percent of the total fatty acids in the

lens membrane. Because linoleic acid is prone to being oxidized, increasing

concentrations in the lens membrane may cause free radical damage.

Linolenic acid is an 18-carbon omega -- 3 PUFA. Spelling wise there is only

a difference of one " n, " but it makes all the difference in the world.

Linolenic acid is the omega-3 fat of vegetable oils found in flax, walnuts

and green leafy vegetables.

The researchers found that when the diet was increased with either of these

fats there was an increased risk of developing cataracts.

American Journal of Clinical Nutrition April 2005;81(4):773-779

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Dr. Mercola's Comment:

The results of this study provide more compelling evidence that a high

intake of polyunsaturated fats, like the ones found in vegetable oils, can

be damaging to your health.

What may be surprising to some of you is that linolenic acid was also shown

to cause damage in this study. A vegetable source of the well-known omega-3

fatty acids, linolenic acid (specifically alpha-linolenic acid) is found in

highest amounts in flax oil.

Flax oil has already been shown to be less effective in regard to treating

inflammation than fish oil is, and this study provides further evidence why

you should choose the latter for your source of omega-3 fats.

The study did not examine whether fish oil had this effect. However,

previous studies have shown that fish oil -- specifically DHA, a type of

fatty acid unique to fish and some forms of algae -- has been found to

provide protection from macular degeneration, another common eye disorder,

while saturated fats, along with polyunsaturated fats from vegetable oils,

do not.

The results of this study provide yet another example of why we need to make

sure we eat a healthy balance of fats. Currently, Americans consume omega-6

and omega-3 fats at a ratio anywhere from 20:1 to as high as 50:1!

At the end of the 19th century, Americans consumed less than one pound of

liquid vegetable oil a year. At the turn of the 20th century, that amount

had increased to 75 pounds per year. Nearly all vegetable oils are loaded

with omega-6 fats. We were simply never designed to eat so many processed

vegetable oil fats. When one combines this with a decline in the intake of

fish and fish oils we have a prescription for disaster.

During Paleolithic times, when humans ate a diet that was most natural for

their bodies, the ratio of fatty acids they consumed was anywhere from 3:1

to 1:1. This is a tremendous difference.

Another key point to keep in mind is that their main sources of omega-3 fats

were seafood and wild game. They had absolutely zero access to the liquid

vegetable oils that Americans are eating today. These oils are produced with

machines that are able to squeeze out every last drop of oil from different

sources like corn and soy.

Not only did early humans not consume corn or soy, the only vegetable, nut

or seed oils they did eat were in a whole-food form, providing only a

fraction of the amount of oil you can find in a tablespoon of such oils

today.

The other primary issue that likely contributed to the incidence of

cataracts in the study was the level of antioxidants in the diet. The

antioxidants prevent the highly perishable PUFAs from being oxidized and

going rancid. If this happens to the PUFAs once they are part of the lens of

your eye you will develop cataracts.

So eating a diet rich in raw vegetables is likely to provide the most

comprehensive source of antioxidants to keep you healthy overall and avoid

the common causes of blindness, cataracts and age-related macular

degeneration. Dark colored fruits, like berries, are also high in these

beneficial antioxidants.

Some tips to assure yourself a balanced intake of fats in your diet include:

Eat small to moderate amounts of raw nuts and seeds.

Eat plenty of raw vegetables and dark colored fruits, like berries, to

increase your antioxidant levels.

Avoid liquid vegetable oils of any kind.

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