Omega 3

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Table of Contents
Omega 3 Influence On The Microbiome
Omega 3 Reduces Inflammation
Omega 3 Against Infections
Omega 3 And Antibiotic Induced Obesity
Omega 3 To Omega 6 Ratio
Omega 3 Dose
Balancing Omega 3 & Omega 6 Example
Omega 3 In Fish Oils Better Than Plant Oils
How Much Oily Fish?
Negative Effects Of Excessive Omega 3
Further Reading And References

Omega 3 Influence On The Microbiome

The positive effect of prebiotic fibres on the microbiome is well documented. A lesser known influencer of the microbiome are omega-3 oils, which are polyunsaturated fatty acids (PUFAs), found in foods such as oily fish. (1)

Animal model studies show a link between gut microbiota, omega-3 fatty acids and immunity in a way that helps to maintain intestinal wall integrity. (2) An enzyme, called alkaline phosphatase (IAP), helps to maintain bacterial diversity, control microbial growth and can help strengthen the intestinal lining. This enzyme is signalled by higher levels of omega-3 fatty acids in our tissues. (3) A study of 876 female twins found that those with higher omega-3 levels had greater bacterial diversity. A separate study of pregnant women confirmed this finding in addition to showing lower markers of intestinal permeability by consuming higher amounts omega-3. (3)

Human and animal studies have found that omega-3 fatty acids positively influence the gut brain axis [which plays a role in IBS] through the composition of the gut microbiota. (2)

A 45-year old healthy physically active male, with a diet of red meat and vegetables, was given a fish protein diet with vegetables, with over 600 mg of omega-3 fatty acids daily. This resulted in significant changes to his gut microbiota, including an increase in butyrate-producing bacteria after two weeks, indicating omegas are very beneficial in the prevention and management of chronic diseases. (3)

A report from June 2017 recommended that omegas and phytochemicals like polyphenols act like prebiotics, such that the definition of prebiotics should be expanded to include them. (3)

In a study of rats, the consumption of walnuts increased bacterial diversity, increased the abundance of Firmicutes, Lactobacillus, Ruminococcaceae, and Roseburia (good bacteria) and reduced Bacteroidetes and Anaerotruncus (bad bacteria). Walnuts are rich in omega-3 fatty acids, phytochemicals, and antioxidants helping to reduce the risk of heart disease and cancer, potentially through its positive effect on the microbiome. (4)

There is an interesting article on the types of fats and their impact on the microbiome here: (5).

Omega 3 Reduces Inflammation

Omega-3 fatty acids can reduce the cause of inflammation by preventing the formation of pro-inflammatory compounds named eicosanoids (11), involved in pain, swelling, warmth (heat) and redness related to inflammation (24). Additionally, they reduce pre-existing inflammation by forming several anti-inflammatory compounds that actively reduce inflammation (14).

The supplementation of omega-3 in patients suffering from inflammatory bowel disease, increased the production of anti-inflammatory compounds in the gut such as short chain fatty acids. (2)

Omega-3 fatty acids anti-inflammatory properties are also linked with the fact that they create gut bacterial diversity which is associated with lower gut inflammation. (22)

Omega 3 Against Infections

Omega-3 fatty acids including LNA and its derivatives (EPA and DHA) have been shown to inhibit the growth of microorganisms through their impact on microbial cell membranes and their antioxidant and immunomodulatory properties. As opposed to antimicrobial drugs, they do not experience evolving antimicrobial resistance. More clinical studies are needed to support the use of omega-3 fatty acids as antimicrobial agents. (6)

In a study, mice fed omega-3 fatty acids demonstrated better survival of sepsis infection than mice fed a saturated fatty acid rich diet. (7)

A study in ‘Lipid Technology’ journal found that omega-3 fatty acids promote the growth of commensal (good) bacteria in the colon. It is these good bacteria than help to crowd out and keep bad (pathogenic) bacteria under control and in lower numbers in the gut. (8)

In a study 4 g mixed eicosapentaenoic acid/docosahexaenoic acid (components of omega-3) in two formulations (soft-gel capsules and Smartfish drinks) produced an increase in helpful bacteria such as Bifidobacterium, Roseburia and Lactobacillus (1).

Mice, deficient in omega-3, had more disease inducing bacteria, creating gut bacterial imbalances and produced less SCFAs (short-chain fatty acids). SCFAs help to maintain the integrity of the intestinal wall. (9)

Polyunsaturated fatty acids (PUFAs) helped the adhesion of probiotic bacteria (L. paracasei) to the inner lining of the intestinal tract in piglets, aiding its inhibitory effect on E. coli infection in the digestive tract of those piglets. (10)

Omega 3 And Antibiotic Induced Obesity

Antibiotics taken early in life can cause a disruption of the microbiome and cause gut dysbiosis which can lead to obesity later in life. Omega-3 fatty acids have been found to reverse antibiotic-induced dysbiosis and significantly reduce body weight gain in a mouse study. This suggests that omega-3s could be used for the prevention of obesity in children who are exposed to antibiotics. (21)

Omega 3 To Omega 6 Ratio

Omega 6 fatty acids can be found in refined vegetable oils added to processed foods. Western diets typically contain 10 to 40 times more omega-6s than omega-3s. Both fatty acids compete for the same enzymes used to convert the fatty acids into their active forms. This means that if you consume high amounts of omega-6, you may need higher amounts of omega-3s. For optimal health, experts believe that the omega-6 to omega-3 ratio should be 2:1 or at least less than 4:1. (9) (12)

Note that omega-3 has a neutral effect on inflammation, whereas omega-6 is pro-inflammatory. This means that high consumption of omega-6 and little omega-3 will increase inflammation. Conversely, a diet high in omega-3 and low in omega-6 will reduce inflammation. (13)

Omega 3 Dose

According to the FDA, daily omega-3 supplementation of up to 3,000 mg per day is safe with no more than 2,000 per day derived from supplements (25). However, the EFSA (European equivalent of the FDA) say that up to 5,000 mg per day from supplements is safe. Overall, the recommendation is a minimum of 250-500 mg combined EPA and DHA each day for healthy adults. (15)

Balancing Omega 3 & Omega 6 Example

Olive oil contains mainly Omega 6, but also some Omega 3. Mackerel contains Omega 3.

The fat composition of olive oil per 100g is in the below table:

TOTAL MONOUNSATURATED (G)	72.96
TOTAL POLYUNSATURATED (G)	10.52
TOTAL OMEGA-3 (G)	0.76
TOTAL OMEGA-6 (G)	9.76

Source: the conscious life, from the USDA National Nutrient Database Standard Reference Release 2 (16)

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1 tablespoon olive oil is 13.5g:
Omega 6 = 13.5/100 x 9.76 = 1.3176g (x 1000 for mg) = 1,317.6mg
Omega 3 = 13.5/100 x 0.76 = 0.1026g (x 1000 for mg) = 102.6mg

1 Mackerel fillet: Omega-3 (EPA & DHA): 3.3g or 3300mg (17)

Consuming 2 tablespoons of Olive Oil per day and 2 mackerel fillets per week gives you:

Omega 6 = 1317.6 mg x 2 x 7 = 18446.4 mg (from Olive Oil)

Omega 3 = (102.6 mg x 2 x 7) + (3300mg x 2) = 8036.4 mg (from Olive Oil and Mackerel)

This is very roughly 2 (Omega 6) to 1 (Omega 3) (2:1) which is the ideal ratio.

Omega 3 In Fish Oils Better Than Plant Oils

ALA, is an essential fatty acid found in plant oils such as flaxseed, soybean, and canola oils. ALA is not made by the body, so needs to come from the foods and beverages that you consume. ALA can be converted into EPA and then to DHA but only in very small amounts. DHA and EPA are found in fish and other seafood. This means that higher amounts of omege-3s can be achieved by consuming fish and seafood rather than ALA containing plants. (18)

How Much Oily Fish?

HEART UK recommend obtaining omega-3s from foods rather than supplements. They suggest aiming to get 500mg of EPA and DHA combined each day. This is about the same as consuming a 140g portion of oily fish per week. (23)

Negative Effects Of Excessive Omega 3

Researchers have discovered that excess amounts of omega-3 fatty acids can lead to a dysfunctional immune response to a viral or bacterial infection such that it impacts the body’s ability to fight pathogens. (19)

Additionally, side effects of excessive fish oil consumption include:

high blood sugar (8 grams/day)
bleeding – nosebleeds (1-5g/day)
low blood pressure (3g can decrease blood pressure)
diarrhoea & flatulence
acid reflux (if supplementing take with meals to avoid effects & split into smaller doses throughout day)
hemorrhagic stroke
vitamin A toxicity (from cod liver oil specifically)
insomnia

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