I’ve been on a sort of vacation from myself lately…which we all need now and then. Just to step out of our own heads for a bit and completely relax. (Not so) coincidentally, this coincided with our family’s beach vacation where I had very limited access to the internet and very plentiful access to sugar, carbs and other naughty foods. I survived, and so did my kids. I’m not advocating a regularly scheduled food free for all…but sometimes it’s nice not to think about what I have to soak or ferment or feed for a little bit.
Anyway, we are back to home cooked meals and reliable internet and just in time for the Real Food Summit
. If you haven’t heard about this, please check it out and register now. You’ve missed the first day but there are still eight more days of free
real food lectures from some of your favorite doctors, authors, nutritionists and bloggers.
I’ll be tuning in whenever I can and I’ll try to report back on some of the more interesting sessions. Yesterday one of my real food heroes, Chris Kresser
, gave a wonderful presentation on the importance of eating fish and seafood. I’ve been meaning to do a post on this for a while now but his presentation gave me the inspiration and the information to make it happen!
Along with being a great protein source, fish and seafood are the only dietary source of long-chain omega-3 fatty acids as well as hard to find nutrients such as selenium, iodine and vitamin D.
Omega-3 has become a household word, and we all know how important omega-3 fatty acids are for good health but just to sum it up for you:
Research shows that omega-3 fatty acids reduce inflammation and may help lower risk of chronic diseases such as heart disease, cancer, and arthritis. Omega-3 fatty acids are highly concentrated in the brain and appear to be important for cognitive (brain memory and performance) and behavioral function. In fact, infants who do not get enough omega-3 fatty acids from their mothers during pregnancy are at risk for developing vision and nerve problems. Symptoms of omega-3 fatty acid deficiency include fatigue, poor memory, dry skin, heart problems, mood swings or depression, and poor circulation. (source)
However, it’s a bit more complicated than just getting your omega-3s…
Omega-6 to Omega-3 Ratio:
Traditionally we had diets high in omega-3 and low in omega-6 fatty acids…a ratio roughly between 1:1 & 3:1. Many feel that this ratio helped protect us from modern diseases of inflammation. When the industrial revolution made it easy to process grains and seeds, vegetable oils began to be marketed as healthy alternatives to animal fats. Around this same time, industrial farms were popping up and moving their cattle to a grain based diet. This diet makes beef disproportionately high in omega-6s. Today the ratio of omega-6 to omega-3 in most American diets is somewhere between 10:1 & 25:1.
So this begs the question…
What’s the Problem with Omega-6?
Omega 6 fatty acids are pro-inflammatory while omega-3s are anti-inflammatory. Because they compete for the same conversion enzymes (the little guys that help to convert omega-3s into EPA & DHA), a diet high in omega-6s will essentially steal the conversion enzymes away from the omega-3’s and the body will have difficulty converting the essential omega-3s after a while. This creates a chronic inflammatory environment in the body and makes us prone to modern diseases of inflammation such as cardiovascular disease, type II diabetes, obesity, cancer, depression and anxiety to name a few.
“The increase in world linoleic acid consumption—that’s omega-6—over the past century may be considered a very large uncontrolled experiment that may have contributed to increased societal burdens of aggression, depression and cardiovascular mortality.” –Dr. Joseph Hibbelen, NIH
It’s no secret that omega-6s have this affect. In fact, over-the-counter anti-inflammatories work to “reduce the formation of inflammatory compounds that are derived from omega-6 fatty acids.”
Now back to the fish…
What About Nuts & Seeds?
While foods like walnuts and flaxseeds are sources of alpha-linoleic acid (ALA) these sources are not converted efficiently in humans. Less than 5% of ALA converts to EPA and less that 0.5% of ALA converts to DHA. If a person has other disease factors (stress, nutrient deficiencies etc.) that conversion may be even lower. Several studies have found that ALA supplements do not raise DHA levels significantly and that nutrient deficiency further decreases conversion. Therefore, it may be wise to consider including animal sources (i.e. fish) of omega-3 in your diet lest you find yourself in a chronic inflammatory state.
Other Benefits of Fish:
Most people are deficient in the following micronutrients which are all found in fish and seafood:
- Iodine: supports thyroid function, metabolism, gut function & immune health
- Selenium: important antioxidant enzyme which regulates thyroid and increases immunity. FYI Brazil nuts are the highest source of this nutrient! Because selenium binds with mercury, mercury containing fish are not a good source, but the flip side of this is that the selenium protects us from the oxidative brain damage associated with mercury ingestion.
- Vitamin D: strengthens bones, balances the immune system and lowers disease risk. We can get this from the sun but conversion is not the same for everyone. Inflammation and obesity can prevent proper conversion.
How Much Fish and What Kind?
If you eat a lot of processed foods, cook with vegetable oils and eat at restaurants a lot your omega 6s are likely very high. In this case you are going to need to eat a lot of fish to balance out the omegas in your diet. If you have a more whole food diet, Chris Kresser recommends 1 lb of cold water fatty fish/week. These are the highest in the long-chain omega-3 fats and include: salmon, mackerel, herring, and sardines.
Is It Safe: What About Mercury, Dioxins and PCBs?:
Mercury is definitely a neurotoxin and we should limit exposure (especially if pregnant or otherwise at risk) however, some of the mercury hype is not entirely accurate because it ignores the role of selenium. When selenium and mercury are present together the mercury can not bind to body tissue. There are very few fish that have a “Negative Selenium Health Benefit Value
” (SeHBV) meaning that they have more less selenium than mercury. A few include: tarpon, marlin, swordfish, shark and pilot whale.
Dioxins and PCBs are other toxins that should be avoided, as they have a strong link to cancer, but fish are not a high source of these chemicals. In fact, factory beef and chicken have a much higher level of these toxins. Research shows that the small risk of these toxins seems to be outweighed by the benefits…specifically the protection against heart disease.
Can I Just Take Fish Oil?
You can, but it’s not as effective. Our body wants to absorb nutrients from whole foods…it’s how we are made. One study found 9 times more absorption of DHA & EPA from whole fish than fish oil supplements. Also, fish contains other nutrients not present in fish oil.
What About Overfishing?
Eat Well, Be Well,
This post was shared on Monday Mania
with The Healthy Home Economist.