title: A dietary cholesterol challenge study to assess Chlorella supplementation in maintaining healthy lipid levels in adults: a double-blinded, randomized, placebo-controlled study.
abstract: 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.
  
  
  
  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.
  
  
  
  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).
  
  
  
  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.
  
  
  
  WHO International Clinical Trials Registry Platform ( KCT0000258 ).
authors.affiliation: Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, 03760, Republic of Korea.
authors.forename: Sangmi
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, 03760, Republic of Korea.
authors.forename: Joohee
authors.initials: J
authors.lastname: Kim
authors.affiliation: Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, 03760, Republic of Korea.
authors.forename: Yeni
authors.initials: Y
authors.lastname: Lim
authors.affiliation: Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, 03760, Republic of Korea.
authors.forename: You Jin
authors.initials: YJ
authors.lastname: Kim
authors.affiliation: Department of Food Science and Technology, Seoul National University of Science and Technology, Seoul, 01811, Republic of Korea.
authors.forename: Ji Yeon
authors.initials: JY
authors.lastname: Kim
authors.affiliation: Department of Nutritional Science and Food Management, Ewha Womans University, Seoul, 03760, Republic of Korea. orank@ewha.ac.kr.
authors.forename: Oran
authors.initials: O
authors.lastname: Kwon
mesh_terms: D015992:Body Mass Index; D002338:Carotenoids / Q000097:blood; D002708:Chlorella; D002791:Cholesterol, Dietary / Q000008:administration & dosage*; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D004032:Diet; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood / Q000628:therapy; D008055:Lipids / Q000097:blood*; D008297:Male; D016896:Treatment Outcome; D014280:Triglycerides / Q000097:blood; D055815:Young Adult
chemical_list: D002791:Cholesterol, Dietary; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D008055:Lipids; D014280:Triglycerides; D002338:Carotenoids; C041635:alpha-carotene
keywords: Carotenoids; Chlorella; Dietary cholesterol challenge; Healthy adult