Metabolic health
Delta-5 desaturase index (D5D)
D5D activity index
Included in Complete.
Compare membershipsEstimating an enzyme from the fats it makes.
Desaturases are enzymes that add a double bond, a kind of kink, to a fat's carbon chain. This index estimates the activity of delta-5 desaturase, which turns DGLA into arachidonic acid and helps make EPA. It's calculated from your fatty acid results.
It's an indirect estimate, and diet affects it too.
The enzyme itself isn't measured in a blood test. Instead, the index compares a product with its starting material, most often arachidonic acid divided by DGLA, though the exact formula can vary by lab.
Your genes (including the FADS1 gene) and your diet both influence this ratio. In observational studies, a lower index has been linked with insulin resistance and higher type 2 diabetes risk. These findings come mostly from research and aren't used to guide routine care.
Questions
What does a lower delta-5 desaturase index mean?
It may suggest less conversion of DGLA into arachidonic acid, though diet and genetics can shift the ratio too. It's best read with your individual fatty acids, blood sugar markers, and health history.
Can I change my index?
Diet can shift the fatty acids used to calculate it, and genetic differences also play a role. Research hasn't established whether changing the index itself improves health.
Sources and references
- Warensjö et al., Associations between estimated fatty acid desaturase activities in serum lipids and adipose tissue in humans (Lipids Health Dis, 2009)
- Kröger and Schulze, Delta-5 and delta-6 desaturase activity and type 2 diabetes (Curr Opin Lipidol, 2012)
- Czumaj and Śledziński, Biological role of unsaturated fatty acid desaturases in health and disease (Nutrients, 2020)