Health and Diet

Cod Liver Oil – The Ultimate Immune Booster?

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It’s snot season. Literally, if you have a child in school you know exactly what I am talking about. It seems almost impossible to make it through flu season without getting sick. Oddly enough I have done it, many times. I don’t get sick very often. I made it 40 years without ever catching the flu, (or getting the flu shot). For a while I thought I just got lucky, I thought I inherited an awesome immune system. Until last year …

I got sick a few times. I had a sore throat that turned into an ear infection in November, and my husband brought home influenza in February. (So yeah, I finally caught the flu). Thankfully, I was able to treat all three ailments exclusively with homeopathy. My daughter only developed a mild cough and a runny nose when she had the flu, (which is truly remarkable). When I had influenza I only had a runny nose and some body aches. So we were fortunate enough to have a mild case, (which I attribute to early use of homeopathy and a clean diet). But I have been trying to figure out why we got sick last year, yet somehow avoided getting sick when we lived in South Korea. My husband brought home illness in South Korea a few times, and Lily and I did not get sick from him. It seems that there is one supplement that “may” have made the difference. It is the one supplement that Lily and I temporarily stopped taking last year, (because of a controversy that was going on). This supplement is Cod Liver Oil.

Cod Liver Oil is a nutritional powerhouse. It has high levels of vitamin D and Vitamin A. My daughter and I started taking Green Pasture’s Fermented Cod Liver Oil when my daughter was around 8 months old. I had recently read the book “Cure Tooth Decay”, and wanted to be proactive with the prevention of tooth decay with my daughter. As of this date it has worked, she had her first dental appointment a few months ago and at 3.5 years old her teeth are perfect. Not only does she not have cavities, but the spacing of her teeth are also good. I became familiar with the work of Dr. Weston Price when I was trying to conceive, so I understood the importance of nutrient dense foods. However, I did not take Cod Liver Oil for the immune properties because I have always had a strong immune system. After getting sick a few times last year I am now interested in the immune boosting properties of Cod Liver Oil, and curious about how it affects my family. If we make it through this winter without getting sick, I will never be without Cod Liver Oil again during the winter months.

Proper levels of Vitamin D are supposed to be protective against the flu. I first heard about this many years ago during the nationwide outbreak of the “Swine Flu”, aka H1N1. I was living in Texas at the time, and I was working for an educational company called “High Touch High Tech”. My job entailed visiting different schools in the district to teach children science using “hands-on” activities. I had to teach at a few of the schools that experienced an outbreak. Instead of getting a flu shot, I went to the local health food store to inquire about supplementation. One of the supplements they recommended was vitamin D. (The recommended dose was high, 5,000-10,000 IU a day). I did not catch the flu during this outbreak, though I am pretty sure I was exposed. This alone is not proof of ANYTHING. I also kept hand sanitizer in my pocket at all times and used it constantly. (Washing your hands is recognized as an excellent way to prevent the flu, or any other illness). However, I did find it interesting, and it is POSSIBLE that it helped.

(Note: this is not intended to be medical advice. You should always defer to your doctor before implementing any supplementation).

It is an interesting coincidence that people start getting sick when the weather gets cooler. Is it because their vitamin D levels are low? The best source of vitamin D is the sun. The levels of vitamin D in my body elevate very quickly with exposure to the sun. I know this for a fact because I tested my vitamin D levels this summer.

The first time I tested my vitamin D levels was in February 2016. I tested it from home using a kit I ordered from the Vitamin D council. (The cost was around $50.00). I tested my blood just days before I had symptoms of the flu. (This was just a lucky coincidence). This is significant because my vitamin D levels were low when I caught the flu, (22.2 ng/ml). Is it proof of anything? No, of course not. This was not a controlled experiment, it is only anecdotal, but it is very interesting.

Why were my vitamin D levels that low? It was the middle of winter, so my exposure to sunlight was lacking. I had also stopped taking Fermented Cod Liver Oil. I had recently run out, and I was still investigating some of the scientific data surrounding a controversy about Green Pasture’s FCLO. Some people had reported low levels of vitamin D despite taking FCLO, and I was trying to figure out why. I stopped taking it 2-3 weeks before testing my vitamin D levels, so I am not sure if my vitamin D levels were low because I stopped taking FCLO or low despite taking it.

Around that time I also found out I was pregnant, so I was desperate to raise my vitamin D levels. I had a hard time determining the ideal range of storage vitamin D. It seems like 35-60 ng/ml is the optimal range. All I know is my vitamin D levels were low by all standards. I knew this was not good, especially during pregnancy, and decided to work on raising it. I took vitamin D supplements for many months and was only able to raise my vitamin D levels to just above “normal”. On July 29, my vitamin D levels were only 31 ng/ml. This was very frustrating because I was taking 5000 IU a day, (as recommended by my health care provider). There is a saying that insanity is doing the same thing and expecting different results. Clearly, what I was doing was not working, so I tried something different. I decided to try to raise my vitamin D levels the natural way, by using sunlight.

Before doing this, I made an appointment to have my blood drawn to test my calcium, magnesium, active D, and storage D. (There is a group called the Magnesium Advocacy group which recommended this test). I wanted data, I needed confirmation that it worked. The week before the test I went to the outdoor pool with my daughter to get some sunlight. I was wearing a bikini for maximum sun exposure. (Yes, I did this while I was very pregnant). I went to the pool 3 days that week, during the time when UV B exposure is the highest, (between 12-3), and I spent a minimum of one hour in the sun each time. (I did not use sunblock). During this week I also made sure I sprayed my body every day with magnesium oil, in case my magnesium was low. (I had read that if you are low in magnesium, it can affect your vitamin D levels).

The results of my blood test were surprising. Five months of supplementing and I was barely able to raise my vitamin D levels above normal. One week with at least 3 hours of sun exposure, (without sunblock), and my vitamin D levels skyrocketed. My active D was 48.4 ng/ml. According to some, this is within the “optimal range“.

This was remarkable. I could keep my vitamin D levels high simply by getting a sun tan. I knew sunlight is needed by our body to produce vitamin D, but I never realized how much more effective it is than supplementation).

So I am not sure how much regular vitamin D supplementation really helped me. Maybe the vitamin D supplements I took during the H1N1 outbreak did not help me as much as I thought they did. (I lived in Texas, where the weather was warmer. Maybe my storage D levels were adequate).

So what effect does Cod Liver Oil have on my vitamin D levels? Sadly, I do not know yet. I do plan on testing my storage D levels soon.
(Edit, I tested my vitamin D levels on 1-13-2017 and it was 38.7 ng/ml. The only vitamin D supplement I used was Nutrapro Cod Liver Oil. My levels were almost acceptable. I was nursing all day so my daughter was definitely taking a lot of nutrients from my body. )

So why didn’t I get sick at all in the 5 years I lived in South Korea? (I never had more than a runny nose a few times). I do suspect my vitamin D levels were higher when we lived in South Korea. My hypothesis is based on the fact that I walked everywhere, even in the winter. My husband had a company car, for work, but I did not have one. I walked everywhere even after I gave birth to Lily. In the winter I walked during the hottest part of the day, (which just happened to be the time when the sun was strongest). Of course the exercise also strengthened my immune system too, so there are many variables at play. (This is why anecdotal evidence is not conclusive).

I did start taking Cod Liver Oil when I was pregnant, (Nordic Naturals), and Green Pasture’s Fermented Cod Liver Oil when my daughter was 8 months old. (We took it together). It did seem to help to keep us healthy. There was one instance where my husband had a bad cough that lasted for 3 months. My in-laws came to visit us during that time, and they both got sick for a few days. Lily and I did not get sick at all. At the time I did not suspect it was the Cod Liver Oil because I was eating healthy, and taking probiotics. Lily was exclusively breastfed, and breastmilk has many immune boosting properties.

The only reason I now suspect the Cod Liver Oil may have been a major contributing factor is because we got sick when we stopped taking it last year, (2015-2016). We were still taking probiotics, eating fermented foods, and eating healthy at the time. So I cannot conclude that Cod Liver Oil prevented illness when we lived in South Korea, it is only a hypothesis. It seems to have been a contributing factor.

This fall Lily and I have been taking Cod Liver Oil consistently for around three weeks. During this time my husband was sick with a sore throat and cough. Lily, I, and the baby did not catch whatever “bug” he brought home. (My husband does not take cod liver oil yet). But sick season has just begun; so only time will tell how well our immune systems will perform. I do plan on taking Cod Liver Oil throughout the winter. It will be very interesting to see what affect it has had on our “storage” vitamin D. (I will share the results once I have them).

So a quick summary of my experience with vitamin D

  • Vitamin D supplementation did not raise my storage D levels into the optimal range
  • Sunlight raised my storage vitamin D levels by almost 20 ng/ml in just 3 days
  • The effect of Cod Liver Oil on my storage vitamin D is currently unknown (Edit – it did raise my vitamin D levels). 
  • Fermented Cod Liver Oil and Cod Liver Oil “seem” to be prevent my daughter and I from getting sick

So how is Cod Liver Oil supposed to support our immune system? As I already discussed, Cod Liver Oil does contain vitamin D. This is not the only vitamin contained in this real food supplement. Cod Liver Oil also contains high levels of vitamin A. In fact, the levels of vitamin A are very high. This is one of the reasons for some of the controversy surrounding some of the Cod Liver Oils. (High levels of vitamin A can actually be harmful, especially if you are pregnant). I have read that the synthetic vitamin A is the concern, and the ratio of vitamin A to vitamin D is very important as well. (The Weston Price Foundation has a lot of great information on food based vitamin A, and why it is not harmful). I encourage you to do your own research on this, and of course defer to your doctor before supplementing with any type of Cod Liver Oil.

Dr. Mercola is someone in the “alternative health” circles who thinks we get enough vitamin A from vegetables.The Weston Price Foundation does not agree with him, in fact, there was a heated debate that occurred some time ago about this. Dr. Mercola thinks the only Cod Liver Oil that has an acceptable ratio of vitamin A to D is Carlson’s Cod Liver Oil. (Though he actually recommends krill oil as a source of DHA and special tanning lamps to achieve adequate levels of vitamin D. Of course he sells krill oil and these special tanning beds, so his opinion may be influenced by these factors). He could be right about vitamin A, I have no way of knowing for sure if we get enough vitamin A from vegetables. I definitely get enough A from Cod Liver Oil, since the levels of vitamin A are high. I have never experienced any negative effects while supplementing with Cod Liver Oil.

Do appropriate levels of vitamin A strengthen the immune system? Absolutely. In fact, the WHO recommends the supplementation of vitamin A to prevent complications from the Measles. Vitamin A can enhance antibody production and lymphocyte proliferation. Vitamin A is also a powerful antioxidant, which is important to reduce stress in the body from free radicals.

Cod Liver Oil is also an excellent source of Omega-3 Fatty Acids; DHA and EPA. Though this is not directly connected to the immune system, these fatty acids play an important role in our overall health. In fact, last night I learned that DHA is a “promoter” in the methylation cycle, and important biochemical cycle in our body. Obviously, anything that reduces “stress” in our body will improve our health. If we spend less energy fighting inflammation, we have more energy to fight viruses and bacteria.

With regards to the controversy surrounding Green Pasture’s Fermented Cod Liver Oil, there was a report that was released that suggested the oil is rancid. I researched this extensively and did not find any scientific evidence that Green Pasture’s FCLO is rancid. (Perhaps I will write a post about this, I spent a lot of time reading through all the evidence). My only concern with Green Pasture’s FCLO is the ratio of vitamin A to vitamin D. (Basically, I am not sure what the vitamin D levels are in FCLO). The rat bioassays show the levels of vitamin D are adequate, however, some lab tests showed the levels of vitamin D3 in Green Pastures Cod Liver Oil was lower than expected. So this is something I am still investigating. While I try to sort this out I am taking Nutrapros Cod Liver Oil, which is on the recommended list published the Weston Price Foundation.

So that is my experience with Cod Liver Oil, and vitamin D. The taste of Cod Liver Oil is definitely acquired. (I have yet to acquire it but I still take it). The Green Pasture’s FCLO can be taken in capsules, and I have never “burped” it up, which is a complaint I have heard with regular fish oil. My daughter has surprisingly never complained about taking it, perhaps because she started taking it at a young age. (She is used to it). The taste of the Nutrapro peppermint Cod Liver Oil is not that bad. I did not care for the Nordic Naturals lemon flavored cod liver oil. I have not tried the Carlson’s Cod Liver Oil, the brand Dr. Mercola has mentioned. Don’t skimp too much when purchasing Cod Liver Oil, you definitely want a quality brand. Rancidity and heavy metal contamination can be a concern, so you want to buy from a company that tests for this. I use the list published by the Weston Price Foundation for recommended brands.

Cod Liver Oil and Fermented Cod Liver Oil is not for everyone, some people do not tolerate it very well. One size does not fit all, so take that into consideration, and pay attention to your body if you do decide to try this supplement. (Some people “muscle test” it for compatibility. I have not tried that yet, but it sounds like a good idea).

Do you take Cod Liver Oil consistently? How has it affected the health of your family?

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