Optimal Result: 0 - 0.08 qmol/dL.

Cystathionine is an intermediate dipeptide within the process of transsulfuration. Transsulfuration is the main route for irreversible homocysteine disposal, glutathione production, and energy. The initial step involves the enzyme cystathionine β-synthase enzyme (CBS). This reaction requires nutrient cofactors such as vitamin B6 and iron. Cystathionine is then converted to cysteine, and eventually goes on to either make glutathione or feed the Kreb’s cycle. Currently, there is no known source or physiologic function for cystathionine other than serving as a transsulfuration intermediate. Some literature suggests that cystathionine may exert protection against endoplasmic reticulum stress-induced tissue damage and cell death, but studies are sparse.


- Maclean KN, Greiner LS, Evans JR, et al. Cystathionine protects against endoplasmic reticulum stress-induced lipid accumulation, tissue injury, and apoptotic cell death. J Biol Chem. 2012;287(38):31994-32005.

- Lamers Y, Williamson J, Ralat M, et al. Moderate dietary vitamin B-6 restriction raises plasma glycine and cystathionine concentrations while minimally affecting the rates of glycine turnover and glycine cleavage in healthy men and women. J Nutr. 2009;139(3):452-460.

- Obeid R. The metabolic burden of methyl donor deficiency with focus on the betaine homocysteine methyltransferase pathway. Nutrients. 2013;5(9):3481-3495.

- Stabler SP, Lindenbaum J, Savage DG, Allen RH. Elevation of serum cystathionine levels in patients with cobalamin and folate deficiency. Blood. 1993;81(12):3404-3413.

- Blom HJ, Smulders Y. Overview of homocysteine and folate metabolism. With special references to cardiovascular disease and neural tube defects. J Inherit Metab Dis. 2011;34(1):75-81.

- Wu XY, Lu L. Vitamin B6 deficiency, genome instability and cancer. Asian Pac J Cancer Prev. 2012;13(11):5333-5338.

What does it mean if your Cystathionine result is too low?

Abnormalities within the methylation cycle can result in lower levels of cystathionine. Low levels of SAM, or methylation imbalances, result in the body preferentially deferring transsulfuration to maintain methylation. Because the CBS enzyme requires vitamin B6 as a cofactor, deficiencies in vitamin B6 may result in lower cystathionine.

What does it mean if your Cystathionine result is too high?

Because cystathionine is an intermediate of the transsulfuration pathway, elevation of this biomarker may indicate a downstream backup of the transsulfuration pathway. Conversion of cystathionine to glutathione, or other transsulfuration metabolites, requires necessary cofactors, such as vitamin B6, zinc, glycine, and magnesium. Therefore, transient elevations of this metabolite may indicate increased need for these cofactors.

Elevated cystathionine may be seen in individuals who have a CBS SNP which upregulates this enzyme and therefore upregulates the conversion of homocysteine to cystathionine.

Elevated S-adenosylmethionine (SAM) directly upregulates the CBS enzyme leading to higher cystathionine levels.

Dimethylglycine (DMG) or trimethylglycine (betaine) supplementation contribute to maintaining methylation. If the methylation cycle is adequate, transsulfuration is then upregulated. With this, supplementation of DMG or betaine have been associated with elevated cystathionine.

Elevated homocysteine may increase its metabolism into transsulfuration. Therefore, in vitamin B12 and folate deficiencies which result in high homocysteine, cystathionine might also be elevated.

10 000+ happy customers
100% satisfaction
★ ★ ★ ★ ★ customer support

Understand blood, stool, and urine medical results from all your laboratories.

Upload Your Personal Results

Upload Personal Results

Monthly plan

Annual plan

Own it for life

  • Subscription
  • Data entry service included

    Data entry service

    Our exclusive data entry service is a convenient way to get your results into your private dashboard. Simply attach an image or a file of your lab test results, and one of our qualified data entry team members will add the results for you. We support all sorts of files, whether PDFs, JPGs, or Excel. This service is excellent whether you have a lot of reports to upload or are too busy to do the data entry yourself.

  • Instant interpretation
  • Use free data entry form

    Free data entry form

    We strive to make the data entry process easy for you. Whether by offering dozens of templates to choose from that pre-populate the most popular laboratory panels or by giving you instant feedback on the entered values. Our data entry forms are an easy, fast, and convenient way to enter the reports yourself. There is no limit on how many lab reports you can upload.

  • 4000+ biomarkers explained
  • Nutrition recommendations
  • Cancel anytime


$15 /month

billed every month

  • monthly
  • $15 per report
  • ✓ Instant interpretations
  • ✓ 4000+ biomarkers explained
  • ✓ Nutrition recommendations
  • ✓ Free data entry form
  • ✓ Unlimited data
  • ✓ $15 data entry service
  • ✓ Cancel anytime

Most popular

Data entry included


$79 /year

$6.60/month billed annually

  • yearly
  • 5 reports free
  • ✓ Instant interpretations
  • ✓ 4000+ biomarkers explained
  • ✓ Nutrition recommendations
  • ✓ We enter 5 reports for you
  • ✓ Yearly subscription
  • ✓ Cancel anytime

Data entry included


$250 /once

own it for life

  • pay once
  • 10 reports free
  • ✓ Instant interpretations
  • ✓ 4000+ biomarkers explained
  • ✓ Nutrition recommendations
  • ✓ We enter 10 reports for you
  • ✓ No subscription
  • ✓ Dedicated support
  • ✓ Unlimited access

Are You a Health Professional?

Get started with our professional plan

Welcome to Healthmatters Pro.

Save time on interpreting lab results with the largest database of biomarkers online. In-depth research on any test at your fingertips, all stored and tracked in one place. Learn more

Pro Monthly Plus

for health professionals

  • ✓ Track multiple clients results
  • ✓ No setup fees
  • ✓ No hidden costs
  • ✓ Instant interpretations
  • ✓ 4000+ biomarkers explained
  • ✓ Includes data entry service
  • ✓ Personal training and support
  • ✓ Cancel anytime

$75 per month

Use promo code to save 10% off any plan.

We implement proven measures to keep your data safe.

At HealthMatters, we're committed to maintaining the security and confidentiality of your personal information. We've put industry-leading security standards in place to help protect against the loss, misuse, or alteration of the information under our control. We use procedural, physical, and electronic security methods designed to prevent unauthorized people from getting access to this information. Our internal code of conduct adds additional privacy protection. All data is backed up multiple times a day and encrypted using SSL certificates. See our Privacy Policy for more details.