Astaxanthin

What it is

Astaxanthin is a carotenoid, more precisely a xanthophyll: a carotenoid that also carries oxygen. The molecule consists of a long chain of alternating double bonds with a ring at each end, and these two rings each carry a hydroxyl and a keto group. It is precisely these four oxygen atoms at the ends that make the difference to all other carotenoids, and the whole article is essentially about that.

It is made from green algae Haematococcus pluvialis, which it stores in large quantities under stress and turns a deep red. Through the food chain it ends up in krill, shrimp, salmon and trout and gives them their color. The pink flesh of a wild salmon is stored astaxanthin, and the dye mixed into the feed of farmed salmon is the same substance.

There are two sources of nutritional supplements, and they are not chemically the same. Natural astaxanthin from algae is predominantly present as a specific mirror image form and is bound to fatty acids. Synthetic, made from petrochemical raw materials, is a mixture of three mirror image forms and is available freely. This difference is not a quibble; it appears again below in the question about the daily amount.

How it works

Why the location in the molecule decides everything

An antioxidant scavenges reactive oxygen compounds before they damage something. That sounds like a property of the material, but it is primarily a question of location. The most sensitive point of attack in the cell is the Cell membrane: Their fatty acids themselves carry double bonds and can be oxidized in a chain reaction in which each damaged molecule attacks the next. An antioxidant is only useful here if it is located where the reaction takes place.

And here lies the special feature. X-ray diffraction measurements on model membranes show that carotenoids are classified completely differently depending on the structure. Beta-carotene, which carries no oxygen atoms, lies entirely in the fatty core of the bilayer. Astaxanthin, on the other hand, stretches the membrane lengthwise and extends into the aqueous phase on both sides with a ring group. In the same experiments, astaxanthin suppressed lipid peroxidation while beta-carotene increased it.

The same ranking comes from an independent direction. When carotenoids in liposomes were tested against peroxyl radicals, the oxygen-carrying xanthophylls provided the best protection and the pure hydrocarbon carotenoids provided the worst protection. It was not the number of double bonds that mattered, i.e. not the theoretical ability to donate electrons, but rather the structure of the end groups and thus their location in the molecular structure.

In practical terms, this means: Astaxanthin covers an area that Vitamin E and beta-carotene cannot be reached. Vitamin E sits with its head on the surface and its tail in the fat core, but does not reach the other side. Astaxanthin is present on both surfaces and in between at the same time. That's the solid core of the matter, and it's significantly less than the advertising makes it out to be.

Where the multiples in advertising come from

“Six thousand times stronger than Vitamin C” and similar numbers come from a single laboratory experiment: the ability to quench singlet oxygen in a solution. Singlet oxygen is one of several reactive forms; the measurement takes place in a test tube and it says nothing about how much substance reaches the blood, where it is stored and what it does there.

The number is not made up, it is just an answer to another question. Whether this transfers to humans is not decided by the factor, but by the studies in the next section. And they are considerably more sober.

What the studies show

The attempt that dismantled expectation

The cleanest single performance study gave 32 trained cyclists and triathletes with a maximum oxygen intake of 60 ml per kilogram per minute 20 milligrams of astaxanthin per day or placebo for four weeks. This was followed by an hour at half maximum power and a time trial.

The substance arrived: the astaxanthin level in the blood rose from undetectable to 187 micrograms per kilogram. Everything else stayed put. Fat burning didn't change, time trial time didn't change, and the total antioxidant capacity of the blood didn't even increase. This is the rare case of a negative study where you can be sure that the uptake wasn't the problem.

What's left when you add it all up

Two current reviews summarize the status and come to the same two-fold conclusion. Markers for muscle damage and for oxidized proteins decrease measurably under astaxanthin. Performance, measured as oxygen uptake, time trial or maximum power, does not.

The contradiction is only apparent. Blood creatine kinase measures how much has come out of damaged muscle cells, not how well someone trains the next day. The fact that a marker falls is an indication of a mechanism, not a result. The question between the two is whether the difference is big enough to get somewhere, and the answer to astaxanthin has so far been no.

There is also a theoretical objection to utility here. The training stimulus works partly through oxidative stress, and high doses of antioxidants can weaken the adaptation to endurance training. This has been shown several times for vitamins C and E, but has not been investigated for astaxanthin. Who in Endurance training should take this into account instead of ruling it out.

Blood lipids

In addition to sport, there is a finding that is independent of it. In a blinded study of 27 overweight adults over twelve weeks, astaxanthin decreased LDL cholesterol and apolipoprotein B, while not a single blood lipid value changed in the placebo group. At the same time, two markers for oxidative damage fell and overall antioxidant capacity increased.

27 participants are few, and a single finding is not proof. But the direction fits the mechanism: The oxidation of LDL particles is the step by which a transport vehicle becomes a deposit, and that's exactly where the substance sits.

Dosage

• 4 to 12 milligrams a day. The range examined is from 4 to 28 milligrams, with no apparent additional benefit above.
• With a fatty meal. The substance is fat-soluble; without fat in the stomach, some of it will not reach the stomach. This is the most common application error.
• The level builds up over weeks; there is no acute effect before training. Assess after four weeks at the earliest.
• Pay attention to the origin. Of course Haematococcus pluvialis, not synthetic. The safety data in humans comes almost exclusively from the natural form.

Side effects

Here the section is exceptionally short, and for good reason. A safety review evaluated 87 human studies and found no safety concerns for natural astaxanthin. 35 of these studies alone used 12 milligrams a day or more without any adverse effects. The overview of oxidative stress also reported no events in seven studies.

The contradiction in the permissible daily amount. What happens: nothing in the body, but something on paper. The European authority has derived a tolerable daily intake of 2 milligrams, while over-the-counter preparations contain 12 milligrams and approvals in other countries range up to 24 milligrams. What it depends on: The 2 milligrams come from animal experiments synthetic Astaxanthin, and this is a different mixture of mirror image forms than that from the algae. The authors of the safety overview therefore consider the transfer to be inadmissible and demand a separate derivation for the natural form. What follows from this: A preparation above 2 milligrams is not a violation of the law and is not a known risk, but the numbers on the package and the authorities' numbers do not mean the same molecule. What you can do: The origin is on the package, choose naturally derived astaxanthin and thus stay in the range to which the human data actually relates. If you want to strictly follow the official number, stick to 2 to 4 milligrams, but then forego the dose that most studies have used.

Reddish discoloration of the skin. What happens: Carotenoids are stored in the subcutaneous tissue, in very high quantities and over a long period of time skin thereby discoloring. This is well known for beta-carotene. What it depends on: quantity and duration. The effect of astaxanthin did not arise as a problem in the human studies evaluated, which is also due to the fact that the usual amounts are orders of magnitude lower than those at which beta-carotene causes color. What you can do: If you notice it, it is harmless and will go away after you stop using it. A dose reduction is sufficient, discontinuation is not necessary.

What is often warned and rarely proven. There are indications of falling blood pressure and inhibited blood clotting, usually with the recommendation to stop taking it before operations. Both come from animal and cell experiments; controlled evidence on humans is lacking. This should be written down and not supported. What you can do: Anyone who takes anticoagulant medication or is about to have an operation mentions the preparation like any other; this is normal practice and costs nothing. No further caution can be derived from the data.

Classification

Astaxanthin is the most interesting mechanism with the thinnest outcome in this area. The thing with the membrane is real, has been measured independently several times and actually explains why the material can do something Vitamin E and beta-carotene cannot. However, it is a long way from there to an effect that someone notices during training, and the existing studies have not covered it.

Who it's worth for: Anyone who has covered the basics, who takes the substance because of the blood lipids or skin and who wants to make a small, well-tolerated bet on a well-founded mechanism. Who it's not for: Anyone who expects more strength, more endurance or noticeably less muscle soreness. Both were checked and neither came out.

The material is therefore a good example of a rule that helps in this area more often than any individual study: a convincing mechanism predicts that something will happen could. He doesn't say whether it will happen.

This article was created using AI systems. Find out more