I found some info on cod liver oil. It used to be an old fashioned elixir that moms would force on their kids, I had no idea that when I put in a search there would be so much present and almost lyrical info, it is apparently very much still an item of use. Of course. it probably doesn't have nifty bottles like Excedrin that one can use to collect all sorts of (eeeew) interesting stuff....
COD LIVER OIL SIDE EFFECTS AND BENEFITS
Cod liver oil is a good source of vitamin A, vitamin D and omega-3-fatty acids. Vitamin A plays an important role in the healthy functioning of the immune system and to resist bacterial and viral infections. Vitamin A is also essential for good eye-sight. Vitamin A deficiency may lead to dry eyelids and poor night vision. Vitamin D helps maintain strong and healthy bones. And recently, some studies show that Vitamin D helps ward off many types of cancer, such as lymphoma, prostate, lung and skin cancers. [4] Combination of vitamin D and calcium may prevent fragility fracture in elderly. [9] Omega-3 fatty acids have anti-inflammatory activities and help relieve the arthritis symptoms and other inflammatory conditions. However, since both vitamins A and D are fat-soluble, the side (toxic) effects can be serious, if you are overdosed.
A high quality cod liver oil is pale-yellow, thin, oily liquid with fishy taste.
What studies have been done in the past?
Do you why some doctors suggest pregnant women to take cod liver oil? There are too many reasons for pregnant women to take cod liver oil. A study shows maternal intake of cod liver oil early in pregnancy associated with a higher birthweight. Usually, higher birthweight indicates a lower risk of diseases later in life. [3] There is another reason-if you want to have a smart kid. In a study of rat, fish oil supplementation during pregnancy improved cognitive performance and maintained glucose levels into adulthood. [7] Maternal intake of very-long-chain n-3 polyunsaturated fatty acids (cod liver oil) during pregnancy and lactation was found favorable for later mental development of children.[8] Cod liver oil taken during pregnancy was found to assciate with reduced risk of Type I diabetes [ a survey (85 diabetic subjects and 1,071 controls] [10]
Some doctors also love to suggest cod liver oil to kids. In one study, cod liver oil together with multivitamin-mineral and selenium was found to be effective in chronic/recurrent sinusitis (children). And, cod liver oil was well- acceptable to the children in this study. [5] In another study, children received 1 teaspoon of cod liver oil per day and one half-tablet of multivitamin-mineral had a statistically significant decrease in the mean number of upper respiratory tract visits over time, while the control group had no change in this parameter. The cod liver oil was also well tolerated in this study, 70%of children completed the 5-6 month course of cod liver oil. [6] A study of 545 childhood-onset type 1 diabetes and 1668 population control subjects in Norway shows the use of cod liver oil in the first year of life associated with a significantly lower risk of type 1 diabetes. [11]
Lipid disorders and increased oxidative stress may exacerbate some complications of diabetes mellitus. Some ingredients in cod liver oil such as antioxidants, PUFAs, EPA and DHA may help protect the cells from the destructive effect of increased lipids and lipid peroxidation products.
In a study, diabetic rats were divided randomly into two groups as untreated or treated with cod liver oil for 12 weeks. Plasma glucose, triacylglycerol and cholesterol levels were significantly elevated in the untreated rats. Cod liver oil treatment provided a better control on lipid and glucose metabolism. Cod liver oil also provided better weight gain in diabetic rats. [17]
Another reason is probably the prevention of rickets. The amount of vitamin D activity in a teaspoon of cod liver oil is sufficient to prevent rickets in infants. [12] In a study cod liver oil prevented the development of rickets in 34 (92%) of 37 infants treated for 6 months. [13]
Traditionally, cod liver oil has been used to help relieve the joint and muscule pain. Recently, several studies demonstrate cod liver oil's ability to mimic cartilage destruction in Arthritis. [1] Forty three patients with rheumatoid arthritis took 1g of cod liver oil daily for 3 months. Improvement in morning stiffness, painful and swollen joints were found. Ratings of "good" or "very good" were awarded by 68% of the patients for cod liver oil efficacy and by 95% for cod liver oil tolerability. Eleven patients reported non severse adverse effects during the course of taking cod liver oil. [2] Another study of 4490 cases from the Norwegian Health Survery demonstrated that people with mucoloskeletal pain experienced less pain if they took cod liver oil. [12]
A few studies has shown that cod liver oil helps treatments of nephrotoxicity. In a study, cod-liver oil containing eicosapentaenoic acid helped improvement on microvascular albumin leakage in diabetic patients with albuminuria. [14] Oral supplementation with fish oil prior to and during gentamicin exposure could markedly ameliorate the drug induced nephrotoxicity. [15] In another study, cod liver oil was shown to protect the mice from daunomycin-induced nephropathy by inhibiting oxidative damage. Dietary cod liver oil significantly reduced urinary albumin excretion and ameliorated the histological changes induced by daunomycin. Compared to soybean oil(SO)-fed mice, the increase of tissue lipid peroxide levels was suppressed in cod liver oil-fed mice. Cod liver oil-fed mice showed higher GSH levels than SO-fed mice throughout the experiment. [16]
Cod liver oil may have benefits on circulation. Researchers successfully decreased serum cholesterol, low density lipoprotein cholesterol and triglycerides in18 normolipemic pigs with cod liver oil. [20] In a study of a group known to have coronary artery disease and endothelial dysfunction, dietary fish oil supplementation enhanced endothelium-mediated vasodilator responses in human heart transplant recipients. [19]
SIDE EFFECTS AND WARNINGS
Do not exceed the recommended daily dose of cod liver oil. Vitamins A and D are fat-soluble. Intake of large amounts of vitamins A and D will lead to toxicity.
Consider only cod liver oil supplements with good reputation. European researchers found cod liver oil supplements contained flame retardant chemicals such as pesticides, polychlorinated biphenyls and polybrominated diphenyl ethers. The presence of these chemicals -in cod liver oil and other fish oils are probably due to the contamination of the marine aquaculture with industrial chemicals. Nowadays, some manufacturers distillate the fish oil as to remove the toxic chemicals. [21]
Do not use cod liver oil to stir-fry chicken or other foods. Salmon and cod liver oils produced toxic malonaldehyde, glyoxal and methylglyoxal when these oils were heated at 60 degrees C for 7 days. During cooking (200C 1h), salmon and cod liver oils produced more these chemicals than vegetable oils did, probably, salmon and cod liver oils contain more long chain PUFA such as EPA and DHA.[22]
Cod liver oil may have side effects but they are not serious. Gruenwald J et al reported three cases of non-severe side effects of cod liver oil from their study of 43 patients. [23]
Before taking any supplements, you should consult with your doctor. Quality from products to products varies.