Tag: heart health

Fish oil is good for the heart and the brain

Claus Hancke

August 21, 2006

There is no doubt that fish oil is good for the heart. This has been shown by a new extensive survey on the subject. But no one knows how much is ideal.

The scientific interest for fish oil is enormous. Since September of last year, almost 800 articles about fish oil have been publicised in established journals.

This is with very good reason. Notably, fish oil contains two types of fatty acid, both of which are attributed with having a positive effect against many serious chronic diseases. If this is even in part true, it should be considered very imprudent not to receive fish oil every day. The primary disease that it is believed to prevent is cardiovascular disease, but there is also good reason to believe that fish oil works against, for example, depression, dementia, arthritis, and diabetes, even though there is no concrete evidence as of yet in these areas.

The two fatty acids are called EPA (eicosapentic acid) and DHA (docosahexaenoic acid). Together they compose one third of the contents of fish oil and two thirds of the concentrated fish oil products, which can be found in capsule form.

Much attention has been given to DHA which, contrary to EPA, is found in large amounts in the brain (14% of the cerebral cortex’s fat content) and in even greater amounts in the retina (22%). Breast fed children have much higher concentrations of DHA in their brains than bottle fed children (babies cannot produce DHA themselves). It is hard to believe that there are no consequences of receive too little.

There are an incredible number of adults who take supplements of fish oil daily to maintain their cardiac health.

But does it work?

Six months ago a group of English researchers maintained that it does not. They had looked at all of the relevant studies and then calculated the averages of their results. In their opinion, the results showed that fish oil neither protects the heart nor lengthens life span. This is just the opposite of what was previously believed.

This meta-analysis was strongly criticized and, as discussed in another of The Danish Vitality Council’s newsletters (“Fish Oil – Still indispensible”) there were so many question raised by the analysis that it lacked credibility.

Doubts regarding the dosage
This is now supported by a summary article from the distinguished American Journal of Clinical Nutrition. According to the head authors, a group of researchers undertook an extensive survey, taking “a large step forward” in spreading light into the darkness. There is no longer much doubt that fish oil reduces the overall risk of premature death and the risk of death due to a blood clot in the heart, and that it possibly reduces the risk of stroke.

Completing this survey was an extensive project. The researchers first read summaries of 8,039 scientific articles. They then picked 842 relevant articles from these to be read in their entirety. 46 articles of these 842 met the strict quality requirements and were studied further. The researches requirements regarded the length of the studies (at least one year), the dose of the fish oil given, and proper documentation.

How big are the advantages and how much fish oil should one take? This actually cannot be answered with certainty! The studies surveyed were too different regarding the dose given, the type of participants, the time taken, and so on to answer such questions. It is simply bad form to establish any averages, as the English researchers did. But if one wants to draw conclusions anyway, it is safe to guess that the overall risk of premature death and the risk of death due to cardiac disease can be reduced by 15-20% or more.

It is however nearly certain that fish oil helps those who have had a blood clot in the heart and wish to avoid another. But what about the dose, how much should one take?

Until more information surfaces, we should rely on the American Heart Association’s recommendations, which are based on estimates. Heart patients should receive 1 gr. EPA + DHA daily. This is the equivalent of about two large capsules of 1 gr. concentrated fish oil. Everyone else should receive at least half this amount. This can be achieved by eating fatty fish for dinner 1-2 times weekly.

There is a lot of knowledge lying in wait, not just about fish oil and the heart. More results will surface in the next year. While we wait we wait in the knowledge that it is important to get enough.

By: Vitality Council

References:
1. Wang C et al. n-3 fatty acids from fish or fish-oil supplements, but not á-linolenic acid, benefit cardiovascular disease outcome in primary- and secondary-prevention studies: A systematic review. Am J Clin Nutr 2006;84:5-17.
2. Deckelbaum R et al. n-3 fatty acids and cardiovascular disease: navigating toward recommendations. Am J Clin Nutr 2006;84:1-2.
3. Distribution, interconversion, and dose response of n-3 fatty acids in humans. Am J Clin Nutr 2006;83(suppl):1467S-76S.

www.ajcn.org

Vitamin D Can Be Used As Heart Medicine

Claus Hancke

May 23, 2006

The warnings against direct sunlight in the summer should be taken with a grain of salt. The vitamin D synthesized in the skin in the wonderful sunshine, prevents, amongst other things, weakening of the heart, if we look at the latest research.

Sooner or later in the course of the summer a dermatologist will appear on television to warn against direct exposure to the sun. It may lead to skin cancer and also threatening is the feared, deadly birthmark cancer, the incidence of which has risen dramatically in step with more and more people desiring a tan. This is partly true.

On the other hand it is prudent to be skeptical when someone advices us to act against what is natural. Can it really be true that the sun is so dangerous when people in our part of the world have been far more exposed to the sun through thousands of years?

Vitamin D is made in the skin when it is in the sunlight, but not from September till May, when the sun is too low on the horizon to be used for this in our part of the world. Since our diet only contains minimal amounts of this vitamin, in the wintertime we use the vitamin which has been built up in the skin in the course of the summer. During the winter approximately 85 % of the daily D-vitamin usage is taken from reserves, even in cases where the diet is rich in D-vitamin. All in all, approximately 100 mcg. is used in a day.

But what happens if the reserves are too small?

In the past half-year a number of studies have shed light over the mysteries of vitamin D. According to one study, the vitamin can help against tuberculosis, which we know was a widespread disease in the 19th and beginning of the 20th century, when many people lived under dire conditions in the cities.

Another study of over 14,000 Americans showed that the people with the largest D-vitamin reserves generally had far better lung function than those with the smallest stores. The difference is as big as the difference between ex-smokers and people who have never smoked before. A possible explanation is that the D-vitamin secures the necessary repairs of worn-out cells.

At about the same time, one of the veterans of vitamin-D research, the American Cedric Garland, concluded that now the proof that vitamin D protects against cancer (especially breast cancer, cancer of the colon and prostate cancer) was very strong. Strong enough to make him regard the connection as definite. He has reviewed all relevant research done since 1966.

Weak Heart and Arthritis
His claims can be compared to the fact that David Feldman of Stanford University now wants to conduct an experiment with calcitriol (the active form of vitamin D, which is made in body from vitamin D in the skin or the food) and ordinary arthritis medication against prostate cancer. In laboratory studies he has found that calcitriol slows the growth of prostate cancer by 25 %, while the combination with arthritis medication slows it by 70 %. A true break-through if it is true.

Everyone knows that vitamin D is necessary for the bones, but it is also necessary for the muscles. A deficiency leads to both muscle pain, weak muscles and for example, a tendency to fall in the elderly. But what about the heart? The heart is also a muscle, and weakening of the heart (cardiac insufficiency) because of atherosclerosis or increased blood pressure occurs in as many as 50,000 Danes. It is a dangerous condition with a high mortality rate.

A German study of 123 patients with a weak heart showed that on average they had quite small amounts of vitamin D in their blood stream, close to a deficiency in the traditional sense. Half of them were given supplements of 50 mcg. D3-vitamin each day for nine months. This is five times as much as the elderly are traditionally recommended given, and is also the upper limit, of what is not dangerous to ingest.
The study was too small to show a difference in mortality, but it did show something interesting. It concerns the protein TNF-alpha, which is produced by the white blood cells in connection with inflammation. TNF-alpha is meant to be a major cause of weakening of the heart. In the patients left untreated, the blood’s content of this protein increased by 5 %. In those treated, there was no worsening. This indicates a stabilizing effect on the inflammation.

This is especially interesting for another reason. TNF-alpha is an important cause of pain and swelling in arthritis. So important that new types of arthritis medication, which blocks TNF-alpha, fittingly, are considered wonder-drugs. If vitamin D decreases the effect of TNF-alpha on the weakened heart, maybe the same happens in arthritic joints. This would also confirm the old assumption that vitamin D protects against arthritis.

When in the sun, one should be sensible and avoid sunburns. Stay in the shadow if the sun is very strong and do not lie about for hours in the sun all covered up in greasy sun lotion.

Also important to know is that it is a risk rather than a virtue to stay out of the sun in the summer.

By: Vitality Council

References
1. Schleithof S S et al. Vitamin D supplementation improves cytokine profiles in patients with congestive heart failure: A double blind randomized placebo-controlled trial. Am J Clin Nutr 2006;83:754-9
2. Heaney R et al. Human serum 25-hydroxycholecalciferol response to extended oral dosing with cholecalciferol. Am J Clin Nutr 2003;77:304-10.
3. Moreno J, Krishnan AV, Feldman D. Molecular mechanisms mediating the anti-proliferative effects of Vitamin D in prostate cancer. J Steroid Biochem Mol Biol. 2004 Nov;92(4):317-25

www.ajcn.org
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