Zeaxanthin from wolfberry in hot milk taken up better
What it found
In 12 healthy people, zeaxanthin from wolfberry mixed into hot skimmed milk reached the blood at about three times the level seen with warm milk or hot water.
The zeaxanthin peaked in the blood at 6 hours for all three preparations.
What they found
Studies in people
Hot milk gave highest levels
The hot milk preparation led to zeaxanthin levels in the blood about two to three times higher than the warm milk or hot water preparations. The warm milk and hot water preparations gave similar results to each other.
Timing of peak
For all three preparations, zeaxanthin in the blood peaked at 6 hours after eating, though this varied a little between people.
Wide variation between people
Response varied widely. Four of the twelve subjects showed a very poor or undetectable response to zeaxanthin. Even when these four were excluded from the analysis, the ranking of the preparations stayed the same.
Other findings
Fat not the reason
The authors note that the better uptake from hot milk was not due to extra fat, because skimmed milk was used in both milk-based preparations.
What the authors conclude
“Results showed clearly that homogenisation of wolfberry in hot skimmed milk results in a formulation that has a 3-fold enhanced bioavailability of zeaxanthin compared with both the ‘classical’ hot water and warm skimmed milk treatment of the berries.”
Also in their conclusions
- They conclude that homogenising wolfberry in hot skimmed milk results in a preparation with a 3-fold enhanced uptake of zeaxanthin compared with both the classical hot water and warm skimmed milk treatment of the berries.
- They say the exact mechanism for the enhancement is still unclear and is the object of on-going research.
- They suggest that a food supplement from a natural source with enhanced zeaxanthin uptake is of interest and potential benefit, and that long-term supplementation studies are needed to answer whether increased zeaxanthin intake affects macular pigment density and AMD prevention.
How it was done
Zeaxanthin collects in the macula of the eye, and more there is suggested to lower the risk of age-related macular degeneration. Wolfberry is one of the richest natural sources of zeaxanthin, but the amount the body can take up from foods is low, so the authors wanted to see if a milk-based preparation could improve it.
Twelve healthy Chinese volunteers, aged 21 to 30, took three wolfberry preparations in randomised order on separate days, each containing 15 mg zeaxanthin, with a standard breakfast. The preparations were wolfberry mixed into hot skimmed milk, warm skimmed milk, or hot water, then freeze-dried into powder. Blood samples were taken before and at 2, 4, 6, 7, 8 and 10 hours after eating, with 3 to 5 weeks between treatments.
What it can’t tell you
- This trial measured zeaxanthin levels in the blood over 10 hours after a single dose. It did not measure whether zeaxanthin reaches the eye or affects macular pigment or age-related macular degeneration.
- The study was in 12 healthy young Chinese adults, so the results may not apply to other groups, such as older people or those with different diets.
Who paid
- Authors work at
- The Hong Kong Polytechnic University, Hong Kong
The paper
- Title
- Enhanced bioavailability of zeaxanthin in a milk-based formulation of wolfberry (Gou Qi Zi; Fructus barbarum L.)
- Type
- Randomised controlled trial
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Benzie IF, Chung WY, Wang J, Richelle M, Bucheli P (2006). Enhanced bioavailability of zeaxanthin in a milk-based formulation of wolfberry (Gou Qi Zi; Fructus barbarum L.). The British journal of nutrition. doi:10.1079/bjn20061796Free full textPubMed 16870004DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error