Here's the thing, though: the normal range goes up to 40 or 56, depending on who you ask. I'm only over when you use that older, lower range. ALT would be expected to be over 100 in cases of cirrhosis or whatever.
This website says 55 is high normal, but not out of range:
https://www.emedicinehealth.com/liver_blood_tests/article_em.htm. 56 is the cut-off. Ranges seem to have been slightly increased over the years, which may be due to a higher toxic burden in modern diets (including more social alcohol).
Normal ranges on lab tests are usually calculated by considering the lowest 2.5% and highest 2.5% tested as abnormal, and the mean 95% of all tested as 'normal'. Normal lab ranges also differ from lab to lab, due to different populations tested. And thereby over time even get more adapted to a increasingly unhealthy population. For example NAFDL is almost an epidemic these days, therefore one can't be sure 'normal' ranges means really healthy anymore.
That's why I always try to find out what functional medicine practitioners use as optimal range, and take extraordinary efforts to try to get there. For example optimal range for ALT I noted is 10 - 30 from some practitioner (don't remember who). However, now also Joe Cohen of selfhacked.com created an
www.labtestanalyzer.com ($35,- to sign up for a half year - have no financial ties other than having paid for 1 period myself), where he evaluated the existing literature for 'optimal' ranges, and came up with 17 - 30 IU/L as optimal range for ALT. Already with my 35 of my latest test I ended up in the 'suboptimal' range.
Values in this range increase your all-cause mortality, and liver and heart disease-associated mortality [
R,
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And mentions all drugs, supplements or environmental factors, which could raise or decrease ALT, again with references to check.
By the way, 18 years ago I was diagnosed a fatty liver on an ultrasound in Gaya, India. The technician speculated from an amoebic hepatitis. However, just the 4 years before had 7 malaria attacks (4 of which the at times deathly plasmotium falciparum) and their again liver-taxing treatments. Already 7 years later the fatty liver was gone, but some 'uncirculated nodules' (5 + 8mm) on the right edge of the liver found by ultra-sound. Again some years later these nodules disappeared too. My liver enzymes still fluctuate some. Where it doesn't comfort me that they are still 'normal' for above obvious reasons.