A dietary cholesterol challenge study to assess Chlorella supplementation in maintaining healthy lipid levels in adults: a double-blinded, randomized, placebo-controlled study.
BACKGROUND
Previous animal studies suggested that Chlorella, a unicellular green alga, has a preventive role in maintaining serum cholesterol levels against excess dietary cholesterol intake. This study aimed to conduct a pioneering investigation to clarify this issue in healthy subjects by adopting a dietary cholesterol challenge, which has not been used previously in similar studies of Chlorella in hypercholesterolemia.


METHODS
In this double blind, randomized, placebo-controlled study, 34 participants ingested 510 mg of dietary cholesterol from three eggs concomitantly with a usual dose of Chlorella (5 g/d) or a matched placebo for 4 weeks.


RESULTS
The dietary cholesterol challenge induced consistently higher concentrations of serum total cholesterol (TC, P < 0.001), LDL-C (P = 0.004), and HDL-C (P = 0.010) compared with baseline values, suggesting that the challenge was reliable. Thus, we observed a preventive action of Chlorella in maintaining serum TC versus placebo levels (3.5 % versus 9.8 %, respectively; P = 0.037) and LDL-C versus placebo levels (1.7 % versus 14.3 %, respectively; P = 0.012) against excessive dietary cholesterol intake and in augmenting HDL-C versus placebo levels (8.3 % versus 3.8 %, respectively). Furthermore, serum α-carotene showed the best separation between the placebo and Chlorella groups (R(2)X and R(2)Y > 0.5; Q(2) > 0.4).


CONCLUSION
The results suggest that a fully replicated dietary cholesterol challenge may be useful in assessing the effectiveness of dietary supplements in maintaining the serum lipid profiles of adults whose habitual diets are high in cholesterol.


TRIAL REGISTRATION
WHO International Clinical Trials Registry Platform ( KCT0000258 ).
['Kim|Sangmi|S|', 'Kim|Joohee|J|', 'Lim|Yeni|Y|', 'Kim|You Jin|YJ|', 'Kim|Ji Yeon|JY|', 'Kwon|Oran|O|']
D015992:Body Mass Index D002338:Carotenoids D002708:Chlorella D002791:Cholesterol, Dietary D008076:Cholesterol, HDL D008078:Cholesterol, LDL D004032:Diet D004311:Double-Blind Method D005260:Female D006801:Humans D006937:Hypercholesterolemia D008055:Lipids D008297:Male D016896:Treatment Outcome D014280:Triglycerides D055815:Young Adult
Dietary cholesterol challenge Chlorella Carotenoids Healthy adult