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.

(NotePCBs, 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

5. POWER TO THE PROTEINS, AND ALSO…. ENOUGH IS NOT ALWAYS ENOUGH (health project 99+)

Dear reader,

To summarize this long post: Proteins can be a source for energy intake, but….. their main job is being ‘building blocks of life’ and working hard on hormones, enzymes, body tissues, and immunity. Latest research states that we should more or less double earlier traditional guidelines, up to 1.5 grams per kilo body weight. Which is not easy! Two side notes. 1. Do not eat farmed fish. 2. Do not get fragile when you age; exercise and eat your protein.

1. Energy first (=carbs and fats)

The three groups of macro-nutrients are the center of many discussions about nutrition. I refer of course to fats, carbs (hydro-carbonates) and proteins. Fats and carbs are your main sources for energy-intake: carbs 4 kcal per gram and fat 9 kcal per gram. Our body needs energy (average 2000 kcal daily) and carbs and fats happily and rather easily provide this. Health-wise, there is of course much more to carbs and fats. Yet, their main task is to supply energy and as such the preferred choice of your body. 

2. Building blocks first (=proteins)

Giving energy is, as mentioned, not the main job for proteins. Still, they will become an energy choice when carbs and fats are not available. During prolonged exercise or starvation, they provide 4 kcal per gram, just like carbs. Nonetheless, your body really prefers proteins for other important jobs. These include building and repairing tissues, making enzymes and hormones, and supporting immune role. They are not called ‘building blocks of life” for nothing!

3. Some Facts and Figures for those who really want to be in the know

There are 20 amino acids. Nine are “essential”, meaning that your body does not produce them and can only get them by eating. “Essential” is a confusing term but it is as it is.

All proteins are made up of long chains of amino acids linked by peptide (= chemical) bonds. The specific sequence of amino acids determines the protein’s structure and function.

The 20 amino acids are transformed into tens of thousands of proteins in your body. Actually it is more complicated. First, you eat proteins, which can be animal or plant-based. Then, your body breaks them down into amino acids. Finally, it rebuilds them into the specific proteins you need. Yes, complicated, but that is how nature often works :).

In the end, we have tens of thousands of different proteins in our body. Each one has unique structures and functions. We need all of them. The exact number can vary. However, estimates often suggest that there are over 20,000 protein-coding genes in the human genome (= genetic blueprint). These genes can produce (= synthesize) multiple different proteins through various biological processes.

4. Need to know: how many proteins per gram produce?

I love nuts and fortunately they give on average 20 grams of protein per 100 grams. Meat and chicken even more, but they are not part of my diet. Fatty fish like salmon, cod (leaner), and sardines offer 20 – 25 grams. Vegetables only give 2 grams. Fruits have less than 1 gram. Two eggs (100 grams) contain 13 grams of protein. Looking at this rough overview one sees the challenge with plant proteins. You really need to eat a lot to get enough. Vegetarians should in my opinion seriously consider taking supplements.

5. Differences between animal and plant proteins

Animal proteins are “complete.” They contain all nine essential amino acids, meaning that your body does not produce them. Common dietary sources include meat, fish, poultry, eggs, and dairy. 

Most plant proteins, on the contrary, are “incomplete.” They are missing one or more of the nine essential amino acids. There are a few exceptions like quinoa and soy. Yet, by combining plant proteins (e.g., beans and rice) you can get all the nine essential amino acids. 

Animal proteins are easier to digest for some people and come with distinct nutrients—like omega-3 from fatty fish. Plant proteins can be more difficult to digest but also comes with extra benefits, like providing the all important fiber.

High plant protein intake appears linked to lower chronic disease risks like heart disease and certain cancers. Conversely, there are links between high intake of animal proteins (especially red and processed meats) and higher chronic disease risks.

6. Risks of an overdose

Over consumption of proteins can lead to health risks. Over consumption is subjective and difficult to define as it varies per person. Still, consuming more than 2 grams of proteins per kilogram over an extended period can harm your health. How much is too much also depends on your lifestyle, health history, and protein quality. 

What I read on internet is that most risks include negative impacts on kidneys and dehydration. It also effects calcium intake which can lead to bone problems. Other risks are weight gain and heart issues, especially from excessive red and processed meat intake. 

7. My personal protein approach

On a typical day, I obtain around 65 grams of proteins from my diet. I get 20 grams from fish and 20 grams from nuts. I do not eat meat. There are 15 grams from low fat French quark and 10 grams from other sources. To reach 120+ grams, I rely on carefully chosen plant-based supplements that include all nine essential amino acids. I personally stay well below 2 grams proteins per kilogram. Fortunately, it is not easy to overdose on protein through regular diet alone; only supplements make it possible. 

For solid information on the necessity of increasing protein intake, search for Thomas deLauer on YouTube. He has almost 4 million subscribers.

Tip: spread protein intake over the day. The ideal intake is 20 – 25 grams per session as your body will only process this amount. Space the intake and take the next one at least a few hours later.

8, Side note 1, on fish: I’ve stopped eating farmed fish like tilapia, shrimp, or salmon. I am concerned about antibiotic use in fish farming. Kim and I prefer wild salmon (despite the higher cost), Atlantic cod, sardines and Dutch herring of course!

9. Another side note, on loss of muscle: do not get fragile when you age.

One can not overestimate the importance of healthy tissues regarding healthy aging. Protein serves a crucial task. It constructs and repairs “tissues,” which include muscles, hair, skin, and organs. Physical exercises including resistance training and adequate protein intake supplement reinforce each other.

Maintaining an excellent muscle system, including hard work to stop loss of muscles (sarcopenia) is central. Muscles and physical exercises are a favorite topic of my blogs. Neglecting your muscles is related to so many potential health problems. This is especially true the older you get. For many reasons. Recent studies for example point to a correlation between weak muscles and a higher chance for dementia.

Ok, enough on proteins. Lead a happy and healthy life,

Robert, your health friend

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