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In days of yore, charlatans hawked elixirs promising good health, virility, and even a greater crop yield. Those days are behind us now. Instead, we have health food stores, with shelves stocked with pills, powders, and herbal products. And sure, there’s solid science behind the benefits many of these supplements can offer to make hearty body and mind. But unfortunately, it appears not all of them are what they’re cracked up to be. New findings from a study led by Dr. JoAnn Manson at the Brigham and Women’s Hospital show that when it comes to fish oil and heart disease, or even fish oil and cancer, the magic just isn’t there. And sadly, the same is true for Vitamin D.

New studies show that Fish Oils and Vitamin D are ineffective in preventing cancer
Fish Oils and Vitamin D are ineffective in preventing cancer

Dispelling the Myths of Fish Oil and Cancer

Dietary supplements generally exist outside the scope of the Food and Drug Administration. As such, claims as to what they can and can’t do for the body have thus far been mostly anecdotal. And many of those anecdotes have painted a rosy picture.

“The idea that fish oil and omega-3s are good for your heart has been nutrition orthodoxy for decades,” said nutritionist Monica Reinagel in the Scientific American earlier this year. With fish oil ranked as the third most popular supplement, it’s not hard to see how ingrained those notions are to the public.

Similarly, many have suggested that vitamin D is integral in lowering blood pressure. Others say it decreases the risk of developing diabetes, cancer and heart disease. It’s also been hailed as a treatment for depression. As a result, vitamin D sales have skyrocketed as more and more doctors prescribe for vitamin D deficiencies.

However, nothing dispels myths like a carefully conducted scientific study. The research of Dr. Manson disproves these decades-old claims. As per the government-backed trial on omega-3 fish oils and vitamin D showed, these supplements do not effectively lower cancer and cardiovascular diseases. The relationship between vitamin D and cancer? The relationship between vitamin D and heart disease? Sorry, they’re just not there.

When it comes to vitamin D and cancer, the studies don't point to a connection.
There’s no magic between fish oil and cancer, nor is there any between vitamin D and cancer.

Vitamin D: A Marker, Not Maker

Of course, when it comes to vitamin D, it’s possible we’ve been looking at it wrong all along. The fact is, the body gets vitamin D from a variety of sources, like sunlight, and food such as eggs, milk, and fatty fish. Conversely, people develop vitamin D deficiencies if they smoke, are obese, or are generally in poor health. Perhaps vitamin D does not produce a healthy body, but only a marker of good health.

Furthermore, a 2001 study on calcium and vitamin D determined that most Americans actually get enough vitamin D daily, and the number of deficiencies might have been overblown. A similar study by the United States Preventive Services Task Force also said that it is not conclusive whether vitamin D supplements prevent diseases.

On the other hand, the American Heart Association does not recommend taking fish oil supplements for adults who are not afflicted with any heart diseases. Alternatively, eating more fish is a more realistic way of consuming fatty acids.

Other Potential Fish Oil and Vitamin D Benefits

While science now refutes any suggestions of links between fish oil and cancer, vitamin D and cancer, and both supplements to heart disease, not all is grim. The study did reveal a few potential upsides.

Tangentially, the study indicated that there might be other benefits to fish oils and vitamin D pills. While they may not be preventative, the analysis indicated that vitamin D can help reduce cancer deaths for people who have been taking them for at least two years. There we also fewer incidences of heart attacks and strokes for people who took fish oil regularly.

Health supplements are good, but there's no link between fish oil and cancer.
The assumption of links between fish oil and heart disease and vitamin D and cancer has been proven erroneous.

Another study’s analysis showed that there was a 28% reduction of heart attacks in people who took fish oil. There was a 40% reduction of heart disease in those who do not regularly eat fish and a 77% reduction in heart disease in African-Americans. The study involved almost 26,000 healthy American women and men, monitored for an average of five years.

Continuing Industry Research

There are no significant benefits nor downsides to taking these supplements. However, it is important not to overdose on daily supplement consumption. Overdosing on vitamin D can cause stomach pains, diarrhea, elevated blood calcium levels, bone loss, and kidney failure. Findings in new studies about vitamin C and fish oil supplements are generally inconclusive.

The rest of the world will still have to wait for any critical new findings about battling heart diseases and cancer. Researchers also suggest consulting your doctor for more accurate prescriptions for any supplements you may want to take.

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