Category: fish

21. OMEGA-3 SUPPLEMENTS, OFTEN NO NEED TO TAKE THEM (health project99+)

Somewhere in the East of Venezuela

Summary: 1. Omega-3 fatty acids are important for your health; all your cells use them. 2. Most people are deficient, but the solution is easy for most (change of diet, not taking supplements). 3. Taking high amounts of Omega-3 fatty acids is recommended by many on internet, but this is something you really should check with your doctor. 4. Many supplements are of low quality and can work counterproductive. 5. Higher amounts of Omega-3 fatty acids can have unexpected health consequences like atrial fibrillation.

Your body needs the different Omega-3 fatty acids, especially the EPA, DHA and ALA types. They are essential for a broad range of health benefits. These benefits start with the heart and brain and extend to a healthy cellular structure and function. All your cells use them on a constant basis.

The good news is that you get enough if your diet includes fatty fish twice per week (herring, salmon etc) for the EPA and DHA. For the ALA flax seed or a handful of walnuts daily should be sufficient. The half-life ( = time a compound stays active in your body) of EPA and DHA is approximately 3-4 days. This is excellent. It explains why a few helpings of fatty fish per week give you sufficient Omega-3. This is as suggested by health authorities.

So do you need to take supplements? They are among the most promoted and sold supplements by the industry. However, just like vitamin C, they are easy enough to get through a balanced diet. Really think twice and look at your diet before you decide to take a supplement.

If you do not like fish or are allergic to nuts, supplements might be necessary. I say this with some caution. Omega-3s supplements can be of bad quality, and they often are. They might even cause unwanted effects like triggering attacks of heart rhythm issues. These issues include atrial fibrillation, which has happened to me. 

In blogs like these it is standard practice to refer the reader to his/her doctor. This is often done as part of one’s “cover your ass” policy. However, in the case of Omega-3, it is advisable to do so. Of course, we hope that your doctor is open-minded. We hope they look at supplements and other alternatives in a welcoming way. Which is not always guaranteed.

The Omega-3 index

Experts typically recommend targeting an Omega-3 index between 8% and 12%. Most Americans have on average 4%, much too low and up to 80% are below the 8%. The Omega 3 index is a blood test. It measures the amount of EPA and DHA found in the membranes of red blood cells. A test above 8% is desirable. The solution of course is not taking a supplement, but to improve one’s diet.

Recommended Intake of Omega-3 fatty acids

Various health organizations suggest around 250 to 500 mg combined EPA and DHA per day for adults. This supports heart health. Of course there are differences between children, men, women, patients etc. The figures I use are rough estimates only.

There is no established upper limit for EPA and DHA from dietary sources. However, supplementation guidelines often recommend not exceeding 3,000 mg (3 g) per day. This is to avoid potential side effects. Some go to 5,000 mg (5 g) per day.

Discuss with your doctor what “excessive” means in your case. Taking up to 5000 milligrams per day is considered safe for most people. However, it is definitely not safe for everyone. If you are like me and are susceptible to atrial fibrillation, more than 1000 mg of combined EPA and DHA per day might already be too much.

For ALA there isn’t a specific recommendation. However, on internet I see the following suggestion: 1,600 milligrams per day for adult men. For adult women, it is 1,100 milligrams per day.

Why take more?

Why should you take more than the recommended least quantities? There is a lot of interesting research going on that indicate (not proven!) that higher amounts of Omega-3 fatty acids can contribute to a longer and more healthy life.

One example from reliable internet sources

According to new research Omega 3 and Vitamins D and exercise slows biological aging by several months. Older adults who took 1 gram of polyunsaturated omega-3 fatty acids from algae slowed biological aging. They mixed it with vitamin D (2,000 international units per day) and 30 minutes of exercise three times a week. This combination slowed biological aging by approximately 2.9 to 3.8 months over 3 years.

While omega-3 alone reduced biological age, the combination of all three interventions had an even greater impact. A reduction of a few months in biological aging may seem modest. However, this could have meaningful public health benefits. These include a lower prevalence of certain age-related conditions.

Further research has also suggested that a combination of omega-3, vitamin D, and exercise may lower the risk of cancer.

But as always, approach these conclusions with caution as further research is needed. Very few claims are 100% scientifically proven. 

What I saw on internet are interesting discussions, a lot of promises, but little proven. Treatments are accepted to slow down aging at the molecular level. However, there is no 100% proof that this leads to a longer life. Similarly, there is no guarantee of better health. Still, many hopeful signs.

If you take Omega-3 supplements

Omega-3 supplements are best consumed with meals, particularly meals containing dietary fats, as this enhances absorption.

Check which brands are reputable. Many are not and the supplements they sell are often oxidized and can be damaging to your health. Preferably buy fish oil, not in capsules, in a dark bottle. Store the oil (or capsules) in the fridge, especially when open. You can do that only for 4 weeks. Fish oil is rich in omega-3 fatty acids, which can easily oxidize in heat, light and air

Oil tends to be absorbed better but can be very expensive. You rely on your digestive system to effectively break down the capsule before it can absorb the omega-3. Most brands use pork or beef gelatin, which is very tough and thus harder to break down.

Best sources for Omega-3s fatty acids.

Natural sources should suffice. For EPA and DHA especially cold water fish like herring and wild salmon. Also eggs can contribute. For ALA flax seed, chia seeds, walnuts.

As I said, it is important to know what was the food of the herring or salmon you eat. The nutrition of farmed salmon is very different from the food of wild salmon. As a result, it has much less EPA and DHA.

The same applies to eggs. Eggs from pasture-raised chickens contain 120 mg of DHA and 23 mg of EPA per large egg. This is more than six times the amount provided by the eggs of grain-fed chickens.

For herring (Atlantic), a 100-gram serving typically contains approximately 770 mg of EPA and 1,000 mg of DHA. For salmon (Atlantic, farmed), a 100-gram serving usually provides around 400-700 mg of EPA and around 700-1,000 mg of DHA.

All easy to calculate. Consuming 300 grams of fatty fish per week provides approximately 5,000 milligrams of EPA/DHA. This amount easily puts you above the minimum needed, which is approximately 2,000 to 3,500 milligrams for the week. Add a few eggs and one can be sure not to be Omega-3 deficient.

Half-life

I already mentioned the long biological half-life of EPA and DHA. This means the time it takes for half of a substance to be eliminated from the body. 

For EPA the half-life is estimated to be around 37 to 82 hours. Half-life of DHA is much longer ranging approximately from 72 to 144 hours.

Often you read about a preferred ratio of EPA and DHA of 2:1. Achieving this ratio is difficult, especially if you rely on natural sources only. However, it is more important to ensure adequate overall intake of both omega-3 fatty acids. This is more crucial than focusing on the precise ratio of EPA to DHA. The half-life of ALA is not known.

Bio-availability

The bio-availability of nutrients refers to the extent and rate at which they are absorbed and utilized in the body. For EPA and DHA Omega-3 fatty acids EPA and DHA the natural sources tend to have very high bio-availability. When consumed as part of whole foods, they are present in the form of triglycerides, which are well absorbed. (note: Triglycerides are a type of fat (lipid) found in your blood).

Potential Risks of Excessive Intake

Bleeding Risk: Doses at the high end of omega-3 fatty acids (over 3,000 mg per day) can increase bleeding risk. This is because of their blood-thinning effects. This is especially important for individuals taking anticoagulant medications. Like many people I take these.

Immune Function: Some studies suggest that very high doses of EPA and DHA might suppress the immune system. However, this is not typically reached through diet or normal supplementation. A dysfunctional immune response can lead to a viral or bacterial infection.

Gastrointestinal Effects: Not surprisingly excessive amounts may lead to gastrointestinal discomfort, such as diarrhea, indigestion, or fishy aftertaste. This is the case with many supplements.

Vitamin E and Oxidative Stress: High doses of fish oil may increase oxidation levels. This effect is because of EPA/DHA. This can deplete vitamin E. Some supplements include vitamin E to counteract this.

Pregnancy and Breastfeeding: Pregnant or breastfeeding women should be cautious with fish oil supplements to avoid excessive intake. They should also aim to meet recommended levels for fetal and infant development.

Interactions with Medications: Those on blood thinners, aspirin, or high-dose anti-inflammatory drugs should consult with a healthcare provider. Omega-3 can exacerbate their effects.

What is the use of EPA, DHA and ALA?

EPA (Eicosapentaenoic Acid) plays a crucial role in reducing inflammation and is involved in the production of signaling molecules called eicosanoids, which have various important effects on cardiovascular health and immune system regulation.

DHA (Docosahexaenoic Acid)  is a vital structural component of cell membranes, particularly in the brain, eyes, and nervous system, where it supports cognitive function, vision, and overall neural development.

ALA (Alpha-Linolenic Acid) serves as a precursor to EPA and DHA, providing an essential source of omega-3s in plant-based diets, and is involved in energy metabolism and various physiological processes, although its conversion to EPA and DHA in the body is relatively inefficient.

This is it. A long one, but it helped me a lot.

Enjoy a happy and healthy life and stay critical!

Robert, your health friend

When I still had to wear ties

9. FOUR DRINKS: (C) THE EVENING VEGETABLES SOUP (health project99+)

Summary: thanks to changing habits, by turning solid vegetables into soup, I now easily meet my daily vegetables target. And my body is grateful for it.

1. I don’t like vegetables...

I’ve never been a fan of vegetables. I would tolerate only peas and maybe some carrots. They had to be covered in Dutch Apple Sauce (which is not healthy because of its high sugar content). Potatoes and especially French fries got a pass. They might count as veggies, but peeled and fried, they do not offer much health benefit.

I have known all these years, of course, that vegetables should play a starring role in any healthy diet. My mother said a thing or two about it, if I remember correctly. But, willpower is essential for any lifestyle change and about these green, red and white things the motivation was just lacking. I will write about the importance of will power (and the lack of it) in another blog.

2. But

About six years ago, my wife decided she’d had enough of my veggie aversion. She started making vegetable soup, using fresh or frozen vegetables only. A blend of persuasion and gentle insistence managed to get me to eat it daily. It was a brilliant move and since then, I haven’t looked back. Vegetables are now an integral part of my diet, and the numbers from my annual health tests show the benefits. *(For context, biomarkers are biological molecules that indicate normal or abnormal processes or conditions in the body.)

3. At home we have a diet that is 3/4 liquid

1. Lemon juice to start the day and as a drink in between (1 liter). https://shakethehealthtree.com/index.php/2025/02/25/5-lemons-and-limes-health-project-99/

2. A large smoothie for breakfast and lunch (up to one liter). I already wrote about this morning routine.  https://shakethehealthtree.com/index.php/2025/03/10/9-four-drinks-a-morning-afternoon-smoothie-health-project-99/

3. A fresh soup for the evening, with some carbs and proteins like fish, 0.4 liters. 

4. Two glasses of water/lemon juice with collagen and creatine (0.5 liters), one in the morning with added protein, and one in the evening without extra protein. 

4. Carbs, meat, fish

We aren’t against carbs. They just need to come in the form of whole grains. We prefer these over white bread, white rice, or light pasta. We don’t eat much meat, and when we do, it’s mainly organic chicken. We consume fish more frequently, though less than before due to a variety of increasing concerns ranging from mercury to nano-plastics. And I already wrote about the big role nuts play in my diet.

5. More about vegetables

I enjoy incorporating a variety of vegetables into my meals. I include red beets, broccoli, spinach, carrots, cauliflower, pumpkin, and sweet potatoes. I like to spice things up with a bit of celery or leek—I would use onions, but I’m unfortunately allergic. Instead of combining all these vegetables at once, I prefer selecting a mix that suits my needs. Not always a culinary success, by the way, but that is part of the process. Healthy they always are!

Each vegetable brings its own unique benefits. For example, beets are touted for their potential health properties, including (unproven) anti-cancer claims. Broccoli and spinach offer around 3 grams of protein per 100 grams. Sweet potatoes are particularly impressive, containing 35% fewer carbs than regular potatoes and packed with vitamins and minerals. 

All these vegetables are excellent sources of fiber which is crucial for health. Good to know as it can be challenging to consume fiber in sufficient quantities, just as it is with protein. Life is unfair because if we compare proteins and fiber with sugar, there the opposite is true. Sugar, our common dietary foe is found in many forms in our food and very easy to overeat.

One caveat. Some vegetables have a surprising amount of sugar as well, so be careful. For example, carrots contain 6 grams per 100 grams, beetroot has 8 grams, and pumpkin 5. In contrast, broccoli contains only about 0.4 grams.

6. Preparation

I mostly use frozen vegetables for their health benefits, cleanliness, practicality, and affordability. When I buy fresh, I cook and freeze them for later use.

I start by boiling approximately ½ kg of frozen vegetables. After boiling for a few minutes, I transfer everything into a blender. I then add salt, pepper, two teaspoons of olive oil, and a generous amount of herbs. Once blended, voilà—a delicious vegetable soup is ready, although not always perfect! Too much cauliflower for example is not to my taste :).

Enjoy a happy, tasty and healthy life,

Robert, your health friend

Cool guys in the DRC, when times were more peaceful

3. FISH IS HEALTHY, BUT NOT TOO MUCH PLEASE (health project99+)

Summary: eating fish is healthy. However, due to an increasing number of foreign substances like mercury, one has to limit fish consumption. When I realized this I cut down my fish consumption by half.

Fish: great, but from now on a cautious “yes”

At home, we used to eat fish almost every day over the past five years. The health benefits of fish are well known. However, we neglected important dangers. Issues like PCBs, nano plastics, and mercury are truly concerning. Other heavy metals and antibiotics in farmed fish also worry me as an enthusiastic fish consumer. 

So I dived into this topic to see whether we could continue eating fish every day. The short and sad conclusion is “no”. It was already “no” to farmed fish. We should also avoid fish that is most likely to have high levels of mercury. PCBs and nano plastics are also concerns. This is all easier said than done. When buying fish, the amounts of mercury and other harmful components are not labeled. They probably never will be, as they are difficult to measure. With mercury it is more or less known which fish is mercury heavy and which not. When it comes to farmed fish, you can find out what is wrong. But what about other heavy metals? PCBs? Nano plastics?

2. Why take the risk?

To those who say that the Japanese eat fish almost daily, I admit I have no answer. They argue that Japanese are among the longest-living people in the world. Food and health are complex issues, as I have come to realize over the past few years. 

Not everything is scientifically proven. However, there are many indications of potential negative effects from eating fish more than a few times per week. So, why take the risk? Especially when you can maintain a very balanced diet without consuming fish daily.

3. Do you need fish for your necessary protein intake?

We humans have several other protein sources legumes, nuts, eggs, light French quark, soya milk, seeds, and plant-based proteins. In another blog I wrote that people tend to undereat protein, something that is very harmful especially if one ages. Eating fish helps. Chicken also helps. For us, fish is “just” one of the protein sources. It is an important contributor to a tasty meal.

4. Just to repeat the benefits of fish. It is an excellent source of high-quality protein. It also provides omega-3 fatty acids, especially in fatty fish like herring and salmon. Additionally, it contains vitamins such as vitamin D and B2. It also has minerals like calcium, phosphorus, iron, zinc, iodine, magnesium, and potassium. Omega-3 fatty acids are beneficial for heart health. They may lower the risk of heart attack and stroke. He/she who eats fatty fish a few times per week really should not take Omega-3 supplements. 

One portion of fatty fish can provide a significant amount of EPA and DHA. Fish like salmon, mackerel, sardines, or herring can offer approximately 250 to 500 mg of these nutrients. The exact amount depends on the type and size of the fish. This amount is typically recommended for maintaining overall heart health. Most sources I read talk about two portions per week of fatty fish.

5. Lean (white) fish typically contains much lower levels of omega-3 fatty acids. This is in comparison to fatty fish such as salmon, mackerel, sardines, and herring. Omega-3 fatty acids are primarily found in the fats of fish. White fish are usually much leaner, so they provide fewer omega-3s. They remain a healthy option as they provide high-quality protein, vitamins, and minerals. 

Some examples of lean fish include Cod, Haddock, Pollock, Hake, Flounder, and Sole. Tilapia (but see my critical remarks on farmed fish), Whiting, Bass, and Shrimps are also lean fish. The following white fish are, unfortunately high on mercury: Sea bream, Sea bass and Turbot.

All international health agencies recommend two portions of fish, with a maximum of three (150 grams). At least one portion should be fatty fish, like herring or salmon. The other can be white fish like cod. White fish lack however the all-important omega-3 with EPA (“eicosapentaenoic acid”) and DHA (“docosahexaenoic acid”),

6. Mercury: important to realize the potential impact on your health

In this blog, I delve a bit deeper into one of the dangers of eating fish: mercury. It is a hazardous heavy metal that we primarily ingest through eating fish. Once it reaches the brain, it can remain there for decades, accumulating and impacting the nervous system. Serious stuff. Other heavy metals, PCBs, and nano plastics might be just as dangerous. These topics will be discussed in other blogs.

(Note: PCBs, or Polychlorinated Biphenyls, are a group of man-made organic chemicals consisting of carbon, hydrogen, and chlorine atoms. They were widely used in various industrial and commercial applications. PCBs have been found to have significant environmental and health impacts; studies are ongoing.)

Some things are recent developments, like nano plastics. We know it is a developing health scare worldwide. Its consequences are not yet known. I cannot imagine that it is good for your body. Who wasn’t alarmed to read that the average adult brain now contains a spoonful of nano plastics? Also a topic for a future blog.

7. From mercury to methylmercury: a technical explanation

Mercury is a global pollutant. It enters water bodies for 1/3 through atmospheric deposition. This deposition results from natural events like volcanic eruptions. For 2/3, mercury enters through human activities such as coal burning and industrial processes. 

The legacy of human use of mercury has caused mercury to be released into the environment in enormous quantities. These releases amount to hundreds of thousands of tons. The levels of mercury in the atmosphere at the moment are up to 500 % above natural levels. In the oceans, the concentrations of mercury are about 200 % above natural levels.

Mercury can undergo chemical transformations once it is deposited to the landscape. Of greatest concern to fish, wildlife, and humans is mercury’s conversion to methylmercury. This conversion is most common in wetlands that are periodically flooded, where the bacteria that facilitate the process are abundant.

Fish absorb methylmercury from the water they live in and from the organisms they eat. Methylmercury is a highly toxic form that accumulates in fish, especially in long-lived and predatory species.

8, Bioconcentration (or biomagnification) refers to the process by which mercury concentrations increase as they move up the food chain. This process results in higher concentrations in higher-level predators such as fish, birds, minks, and otters. Through bioconcentration, mercury levels can increase by 100 to 1,000 times or more. As a result, even low concentrations of mercury in water can contaminate an entire food chain. This contamination makes fish unsafe for human consumption.

Mercury usage and emissions have been reduced in regions such as Europe and North America. Despite this, environmental levels of mercury are likely to remain high for a long time. This persistence is due to mercury’s long lifetime in the environment and increasing emissions in other parts of the world. These emissions can travel long distances. In fact, about half of the mercury deposited in Europe comes from outside the continent.

The biological half-life of mercury is estimated to be approximately 30 to 60 days in the body. The half-life of mercury in the brain is not entirely clear. However, it is estimated to be as long as approximately 20 years.

9. Fish with high or low mercury level

Mercury levels differ from one species of fish to the next. This is due to factors such as the type of fish, size, location, habitat, diet and age.

Fish that are predatory (eat other fish) are large and at the top of the food chain, and so tend to contain more mercury. This includes tuna and swordfish. Try to avoid them and go for wild salmon, herring, sardines etc.

10. Potential Health impact is serious

The health impacts of mercury are dose-related, but the main concern is its impact on fetuses and young children. Mercury exposure can occur in the womb due to a mother’s consumption of seafood, which can have significant and lifelong effects on a baby’s developing brain and nervous system. This exposure can affect memory, language, attention, and other skills. In Europe alone, it is estimated that more than 1.8 million children are born each year with mercury levels above recommended safe limits.

In adults, chronic mercury exposure can lead to neurological and developmental issues. Symptoms of mercury poisoning can include tremors, memory problems, and cognitive deficits. In severe cases, it can affect kidney function and the respiratory system. Mercury exposure can also potentially impact cardiovascular and immune health in adults.

11. Possible symptoms of methylmercury poisoning may include

Loss of peripheral vision; pins and needles” feelings, usually in the hands, feet, and around the mouth; lack of coordination of movements; impairment of speech, hearing, walking; and/or muscle weakness.

12. Testing

It is possible to measure the levels of mercury in your body through blood tests, urine tests, and hair analysis. The last method is particularly interesting. Measuring mercury levels in hair can provide an estimate of long-term exposure to methylmercury. Hair accumulates mercury steadily as it grows. This reflects exposure over months rather than days. This is useful for assessing chronic exposure.

13. My Experience

For years, we enjoyed our daily fish meals. However, preparing this blog made me realize my naivety during all those years. Yes, fish is healthy. However, it can also carry many harmful substances. These include heavy metals, PCBs, nano plastics, and antibiotics.

We ate tinned sardines and mackerel. We also had deep-frozen cod from the North Atlantic. Of course, we enjoyed sustainably fished fresh Dutch herring and the occasional wild salmon.

It proved to be almost impossible to get hard data on which fish carries which substances. It is probably too complex; I realize this. But, I have read too much worrying news from reliable sources to continue with my current level of fish consumption.

So we decided to cut down on fish. We enjoy Dutch herring once or twice a week. We have wild salmon once a week. Both are oily fish providing omega-3 fatty acids.

Additionally, I will do a hair analysis to check if mercury has accumulated in my body.

Time for dinner, but no fish tonight :). Enjoy a long and healthy life,

Robert, your health friend