A S K D R . A N G E L A

Question of the Week:

Dear Dr. Angela,

My husband and I found a report referring to a study of using Omega 3 to reverse kidney disorders. I am interested in learning the results of the study because my 20-year kidney condition is progressively worsening. It would be great if you can provide us with any information to help combat or slow down this disorder.

Thanks,
Daisy, Davis, CA

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Dear Daisy,

In our current study, we are looking specifically at immunoglobulin A nephropathy, which is a glomerular inflammatory disease. For this disorder it does look like omega-3 fatty acids are helpful to some patients but not all. In our study the aim is to identify for whom the omega-3 fatty acids work and in turn develop a diagnostic of who would be a responder to omega-3 fatty acids. We do not yet have the final results of the study. 

If your kidney disease is inflammatory in nature omega-3 fatty acids may work for you. In either case, omega-3 fatty acids are not a drug, they are simply a kind of fat that humans used to get a lot more of in the diet than is currently available in our food supply. It is estimated that the human diet used to have approximately a 1:1 ratio of omega-6 fatty acids to omega-3 fatty acids. The current Western diet has changed drastically to about a 10:1 ratio! It has been widely hypothesized in the scientific literature by researchers across disciplines that it is this low intake of omega-3 fatty acids that is at least partially causing the rise in inflammatory diseases from atherosclerosis to rheumathoid arthritis to Alzheimer's disease. Certainly, the association studies show a strong trend and many clinical trials show that omega-3 fatty acids are effective at reducing disease risk and progression. 

The reasons for the large shift in the fatty acid ratios are related to the focus of our food supply on grain-based diets, from what we feed our animals to what we feed ourselves, along with a decrease in the intake and diversity of green leafy plants, as well as the dwindling and increasingly mercury-laden fish supply. Omega-3 fatty acids can only be found in appreciable amounts in fish, certain algae, flax seeds, walnuts, and some green leafy plants. These are foods that are consumed at low levels compared to the consumption of grains and vegetable oils, which are enriched in omega-6 fatty acids (with the exception of canola oil, which is a decent source of omega-3, and olive oil which is composed of primarily monounsaturated fat, which is neither omega-3 nor omega-6). What's more, as I mentioned, most of our livestock are grain-fed now rather than grass-fed, which has changed the fat composition of our meat products and eggs as well. 

Since omega-3 and omega-6 fatty acids are the direct precursors to inflammatory lipid signaling molecules, called eicosanoids or oxylipids, that are produced in our bodies in response to injury and stress, they are part of our inflammatory and immune response mechanisms. You have probably heard of prostaglandins and leukotrienes in commercials about asthma and allergy medications. Prostaglandins and leukotrienes are two types of eicosanoids or oxylipids that are derived from omega-6 and omega-3 fatty acids. The omega-6 fatty acid, arachidonic acid (ARA), is a precursor for predominantly pro-inflammatory and much more potent prostaglandins and leukotrienes which stimulate platelet aggregation, immune cell recruitment, and other mechanisms that are meant to reverse cellular damage caused by injury and stress. On the other hand, the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are precursors for predominantly less potent and anti-inflammatory oxylipids. One way to think of it is that ARA is like the gas pedal for turning on the immune system, whereas EPA and DHA are like brake pedals. If the composition of your cell membranes is enriched in ARA and deficient in EPA and DHA this predisposes for uncontrolled immune response, like stepping too strongly on the gas pedal with no way to slow down or stop due to a malfunctioning brake pedal.

The reasons for increased immune system activation in the first place are much more complicated and largely unknown for many diseases, but it is becoming more and more clear that deficiency in the omega-3 fatty acids can lead to an overactive inflammatory response which can potentiate auto-immune diseases and inflammatory diseases.

What does this all mean for you? If your kidney disease is inflammatory in nature (and I would need to know more about your particular condition before I could give you any specific advice) then omega-3 fatty acids may indeed help to tame your inflammation. You can try taking flax seeds/flax seed oil and eating walnuts, which are enriched in a shorter-chain omega-3 fatty acid alpha-linolenic acid (ALA), which acts as a precursor for the longer-chain EPA and DHA. However, not everyone converts ALA to EPA and DHA efficiently, and we currently do not have a diagnostic that can tell you whether you are one of these "non-converters" (along with several UC Davis collaborators, I am currently working on developing this diagnostic as well). If the flax/walnuts don't seem to help, you are likely to be a non-converter, in which case you need to take the long-chain EPA and DHA directly in the form of fish (like sardines), fish oil, or krill oil (tiny shrimp), or there are also some vegetarian versions available that are produced from algae, but they typically contain much less EPA and DHA than does fish oil per capsule. It is important to select a fish oil that is made from small fish such as sardines rather than larger fish such as cod or tuna, because the larger the fish, the more mercury. It is also very important to select a brand that has been tested and purified for contaminants such as mercury and PCBs.

While omega-3 fatty acids are considered safe to consume it is important to consult your physician or health care professional before adding any supplements to your diet because they may interfere with or be contraindicated in your particular condition.

Dr. Angela


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