Albumin above or below normal: causes in athletes and what to do

Athletes often try to correct a deviation of albumin in a biochemical analysis with protein. However, elevated albumin almost always means thickening of the blood, while reduced albumin is most often inflammation, problems with the liver, kidneys or intestine, and not a lack of protein in the diet. The editorial team explains how to work out the cause and what steps are worth taking.

The albumin balance: where it comes from and where it goes

The concentration of albumin in the blood is the result of an equilibrium of several processes: synthesis in the liver, distribution between the vessels and tissues, breakdown and losses through the kidneys and intestine. In addition, the concentration is affected by the volume of plasma in which the protein is «dissolved».

Any link of this chain can shift the result. The liver may produce less protein, the vessels may «let it through» into the tissues during inflammation, the kidneys or intestine may lose it, and changes in the water balance may dilute or concentrate the blood.

Since albumin lives for several weeks, acute changes in concentration over hours and days are almost always associated with water and redistribution, not with synthesis. A persistent decrease over weeks more often points to a problem with the production or loss of protein.

That is why the first step with any deviation is to compare the result with previous tests and with the conditions under which the blood was drawn. This makes it possible to filter out a significant part of the «false alarms».

Elevated albumin: almost always water

True excessive production of albumin by the body practically does not occur. Therefore an elevated result almost always means that the plasma volume has decreased and the protein has become more concentrated. In parallel, such a test usually shows elevated total protein, hemoglobin, hematocrit, sometimes — creatinine and urea.

In athletes the most common causes are inadequate drinking, fluid losses through sweat during training in the heat, cutting weight before weigh-in, and also a test given soon after intense or prolonged exertion. The ACSM recommendations on hydration (Sawka et al., 2007) remind us that even moderate dehydration worsens performance and thermoregulation.

Technical causes also occur: prolonged application of a tourniquet, drawing blood while standing or immediately after climbing the stairs. Thickening of the blood in the tube raises the concentration of all proteins.

What to do with elevated albumin without other symptoms: restore the usual drinking regimen, repeat the test after a day without intense training, sit quietly before blood is drawn. Protein and food supplements have nothing to do with it here: there is no sense in reducing protein intake «because of high albumin».

Reduced albumin: the main causes

Hypoalbuminemia is a much more clinically important condition. A review by Soeters, Wolfe and Shenkin (2019) emphasizes that the main cause of a decrease in albumin in clinical practice is inflammation, not starvation: it reduces protein synthesis by the liver and increases its escape from the vessels into the tissues.

Note: inadequate protein intake is at the end of the list. For albumin to decrease substantially through nutrition alone, the deficiency must be prolonged and pronounced. In an athlete with an ordinary diet, reduced albumin is grounds for looking for another cause.

A pronounced decrease in albumin manifests as edema of the shins, face and eyelids, and in severe cases — accumulation of fluid in the abdominal cavity. Such symptoms require a mandatory visit to a doctor.

Special situations in athletes

Several situations related to sport deserve separate attention, because they can either imitate a problem or, conversely, mask it.

• Physiological dilution:in those trained for endurance, an increased plasma volume can cause an albumin concentration near the lower limit of normal without any pathology.
• Excessive drinking over long distances:overhydration dilutes the blood and can be accompanied by a dangerous decrease in sodium — hyponatremia, a condition requiring emergency care.
• Protein in the urine after exertion:transient proteinuria after intense training is common and benign; therefore a urine test for albumin is not taken after training.
• Hepatotoxic substances:oral 17-alpha-alkylated steroids, alcohol, some drugs and «fat burners» can damage the liver; albumin decreases late in this case.
• Energy deficiency:prolonged calorie restriction with large training volumes can be combined with inflammatory conditions and frequent injuries.

Conclusion: with reduced albumin in an athlete, one should first rule out dilution and training on the eve, and then look for inflammation, damage to the liver, kidneys or intestine.

The ASPEN position stand (Evans et al., 2021) reminds us that albumin cannot be used as a target indicator of nutrition. That is, it will not be possible to «raise albumin» with protein supplements without eliminating the cause, and the goal of treatment is the underlying condition itself.

What to do: an examination plan

If albumin is reduced and there are no obvious explanations, the editorial team advises acting consistently together with a doctor. A minor one-off decrease without symptoms often disappears on a repeat test.

1. Repeat the biochemical analysis on an empty stomach, after a day without training, without excessive drinking before the test.
2. Add total protein, C-reactive protein, liver tests (ALT, AST, GGT, bilirubin), creatinine.
3. Give a morning urine sample for the albumin/creatinine ratio (not after training) — this test is recommended by the KDIGO guidelines for assessing kidney damage.
4. In the case of intestinal complaints — discuss with the doctor an examination for celiac disease, inflammatory bowel diseases.
5. Review the list of medications, supplements and substances that can affect the liver.

The approach to assessing altered liver indicators is described, in particular, in the clinical guidelines of the American College of Gastroenterology (Kwo et al., 2017). The doctor chooses the scope of the examination depending on which deviations exactly are combined with reduced albumin.

Seek help urgently in the case of rapidly increasing edema, shortness of breath, a sharp decrease in the amount of urine, yellowing of the skin, and also confusion, nausea and headache after prolonged exertion with a large amount of fluid drunk.

Editorial conclusions

Elevated albumin in an athlete almost always means thickening of the blood due to dehydration or the conditions of taking the test and is corrected by normalizing the drinking regimen.

Reduced albumin is most often associated with inflammation, damage to the liver, kidneys or intestine, or dilution of the blood, and not with a lack of protein in the diet.

The correct tactic is to repeat the test correctly, add accompanying indicators and, together with a doctor, find the cause, rather than trying to «fix the figure» with protein.

We also recommend reading our materials on what an albumin test shows, on total protein above or below normal, and on hydration during training.

References

1. Soeters PB, Wolfe RR, Shenkin A. Hypoalbuminemia: pathogenesis and clinical significance. JPEN J Parenter Enteral Nutr. 2019;43(2):181–193.
2. Levitt DG, Levitt MD. Human serum albumin homeostasis: a new look at the roles of synthesis, catabolism, renal and gastrointestinal excretion, and the clinical value of serum albumin measurements. Int J Gen Med. 2016;9:229–255.
3. Evans DC, Corkins MR, Malone A, et al. The use of visceral proteins as nutrition markers: an ASPEN position paper. Nutr Clin Pract. 2021;36(1):22–28.
4. Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. KDIGO 2012 clinical practice guideline for the evaluation and management of chronic kidney disease. Kidney Int Suppl. 2013;3(1):1–150.
5. Kwo PY, Cohen SM, Lim JK. ACG clinical guideline: evaluation of abnormal liver chemistries. Am J Gastroenterol. 2017;112(1):18–35.
6. Sawka MN, Burke LM, Eichner ER, et al. American College of Sports Medicine position stand. Exercise and fluid replacement. Med Sci Sports Exerc. 2007;39(2):377–390.