Phytonutrients - Naringin

Question 1

Naringin

Answer 1

Naringin belongs to the group of flavonoids. It is metabolised to naringenin in the gut by intestinal bacteria

Naringin from the Sanskrit term narangi meaning ‘orange’

Question 2

Food sources:

Answer 2

Food sources:
* Citrus fruits (especially in grapefruit, where naringin is responsible for the fruit’s bitter taste). Also found in cooked tomato paste.

Question 3

Caution:

Answer 3

• Grapefruit is contraindicated with numerous medications because naringenin inhibits intestinal CYP3A4 (the pathway used for many pharmaceutical drugs). Its inhibition results in less metabolism and thus higher circulating levels of drugs.

Question 4

Functions:

Answer 4

• Cardiovascular health
• Anti-cancer
• Diabetes

Question 5

Cardiovascular health

Answer 5

Functions:
* Protects the vascular endothelium —antioxidant and LDL-lowering effects. Inhibits atherosclerosis progression.
Therapeutic uses:
* Atherosclerosis (incl. prevention).
* Hyperlipidaemia.

Question 6

Anti-cancer:

Answer 6

Functions:
* ↓ Angiogenesis. Evidence suggests a particular use in prostate cancer.
Therapeutic uses:
* Cancer prevention.

Question 7

Diabetes:

Answer 7

Functions:
* Naringin inhibits ‘aldose reductase’ —an enzyme associated with diabetic complications by directing glucose into pathways producing inflammatory metabolites.
* ↓ diabetic retinopathy and neuropathy.
Therapeutic uses:
* Reduces acceleration and complications of diabetes.