The influence of obesity on the effects of spirulina supplementation in the human metabolic response of Korean elderly
Open accessAbstract
BACKGROUND/OBJECTIVES: Spirulina, a blue-green alga, is widely produced and commercialized as a dietary supplement with bio- and immune-modulatory functions. We have previously shown that spirulina had favorable effects on lipid profiles, immune functions, and antioxidant capacity in healthy Korean elderly. Despite favorable effect of spirulina supplementation, some sub-populations have shown a poor response to supplementation. Obesity is a factor related to poor-response. Therefore, the purpose of this study was to determine the immuno-modulation, antioxidant capacity, and lipid-lowering effect of spirulina in obese and non-obese Korean elderly. SUBJECTS/METHODS: The subjects were 78 elderly aged 60-87 years. In a randomized double blind, placebo-controlled study, subjects were fed either placebo or spirulina daily, at 8 g for 12 weeks. Subjects were divided into the non-obese group and the obese group based on body mass index (BMI) criteria for Asians suggested by the International Obesity Task Force: BMI < 25 kg/m(2) (non-obese) and BMI ≥ 25 kg/m(2) (obese). RESULTS: In the non-obese group, spirulina supplementation showed a significant lowering effect on plasma concentration of total cholesterol and LDL-cholesterol, a significant increase in interleukin (IL)-2 concentration (P < 0.01) and a significant increment (P < 0.05) in IL-2/IL-6 ratio, and a significant increase in total antioxidant status level and a significant decrease in thiobarbituric acid reactive substances level. However, these effects were not observed in the obese group. CONCLUSIONS: These results demonstrated that blood lipid lowering and immune and antioxidant improving response for spirulina supplement was affected by obesity in Korean elderly.
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Written from the paper’s full text.
TL;DR
In a randomized, double-blind, placebo-controlled trial of 78 Korean elderly, spirulina supplementation improved lipid, immune, and antioxidant markers in non-obese participants but not in obese participants. The authors conclude that obesity may reduce the metabolic and immune response to spirulina.
Key findings
- In the non-obese group (BMI < 25 kg/m²), spirulina significantly lowered total cholesterol and LDL-cholesterol, increased IL-2 (P < 0.01), increased the IL-2/IL-6 ratio (P < 0.05 in the abstract; P < 0.01 in the results), increased total antioxidant status (TAS), and decreased thiobarbituric acid reactive substances (TBARS) from 7.12 nmol/ml to 5.37 nmol/ml (time × treatment P < 0.05).
- In the obese group (BMI ≥ 25 kg/m²), no significant changes were observed in plasma cholesterol or triglyceride after intervention.
- IL-2 increased by 33.4% and IL-6 decreased by 14.6% in the obese group, while IL-2 increased by 54.1% and IL-6 decreased by 20.7% in the non-obese group; TNF-α showed no supplementation effects.
- TAS increased significantly in the non-obese group after spirulina and in the obese group after placebo, with no significant time-by-treatment interaction for TAS in either group.
Methods
- Randomized, double-blind, placebo-controlled study; 78 elderly subjects aged 60–87 years (43 male, 35 female) were assigned to spirulina or placebo at 8 g/day for 16 consecutive weeks/4 months (the abstract states 12 weeks).
- Subjects were divided by Asian BMI criteria: BMI < 25 kg/m² (non-obese) and BMI ≥ 25 kg/m² (obese).
- Outcomes included plasma lipids, IL-2, IL-6, TNF-α, TAS, TBARS, anthropometry, and dietary intake; analyses used SAS 9.4, paired t-tests, repeated measures ANOVA, and Scheffe’s post hoc tests at the 5% significance level.
Limitations
- The paper states that the mechanism between obesity and spirulina supplement response is not yet clear, and it is uncertain whether effects are due to obesity-related pathological/immunological changes or to a relatively low spirulina dose for obese body weights.
- The paper states that further studies are needed to determine the mechanism of spirulina on lipid profiles, immune variables, and antioxidant capacity based on BMI.
- Evident from the text: the reported supplementation duration is inconsistent (abstract says 12 weeks; methods and conclusion say 16 weeks/4 months), and baseline differences existed between groups (non-obese spirulina group had higher fasting blood sugar and triglyceride; obese placebo group had higher total energy and carbohydrate intake).
Model-written summary. Check it against the paper before relying on it.
Integrity signals
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Claims the paper makes
0 of 15 cited sources checked · 0 supported · 0 flagged
- Findingown data
In non-obese Korean elderly, spirulina supplementation significantly increased the IL-2/IL-6 ratio (P < 0.01).
“and a significant increment (time × treatment interaction, P < 0.01) in IL-2/IL-6 ratio”
Quote in the paperSubstantial claim - Findingown data
No significant time-by-treatment intervention for TAS was observed in either BMI group.
“No significant time-by-treatment intervention for TAS was observed in either group.”
Quote in the paperNot a substantial claim - Findingown data
In obese Korean elderly, spirulina supplementation significantly increased IL-2 after 4 months.
“In the obese group, like in non-obese subjects, the level of IL-2 was significantly increased after 4 months of spirulina supplementation.”
Quote in the paperNot a substantial claim - Findingown data
For TNF-α, no effects of supplementation with either placebo or spirulina were observed.
“For TNF-α, no effects of supplementation with either placebo or spirulina were observed.”
Quote in the paperNot a substantial claim - Findingown data
The increase in IL-2 was greater in non-obese than in obese subjects (54.1% vs 33.4%).
“Specifically, in the obese group, IL-2 increased by 33.4% and IL6 decreased by 14.6%, while IL-2 increased by 54.1% and IL6 decreased by 20.7% in the non-obese group.”
Quote in the paperSubstantial claim
- Findingown data
In non-obese Korean elderly, spirulina supplementation significantly increased total antioxidant status (TAS).
“the TAS level was significantly increased in the non-obese group after spirulina supplementation”
Quote in the paperSubstantial claim - Findingown data
In non-obese Korean elderly, spirulina supplementation significantly lowered plasma total cholesterol.
“In the non-obese group, spirulina supplementation showed a significant lowering effect on plasma concentration of total cholesterol and LDL-cholesterol, while no changes were observed in the placebo group.”
Quote in the paperSubstantial claim - Findingown data
In non-obese Korean elderly, spirulina supplementation significantly increased IL-2 concentration (P < 0.01).
“In non-obese subjects, spirulina supplementation resulted in a significant rise (time × treatment interaction, P < 0.01) in IL-2 concentration”
Quote in the paperSubstantial claim - Findingown data
In non-obese Korean elderly, spirulina supplementation significantly decreased TBARS level from 7.12 nmol/ml to 5.37 nmol/ml.
“TBARS level was decreased from 7.12 nmol/ml to 5.37 nmol/ml in the non-obese group after spirulina supplementation. A significant time-by-treatment intervention for TBARS was observed in the non-obese group (P < 0.05).”
Quote in the paperSubstantial claim - Findingown data
In non-obese Korean elderly, spirulina supplementation significantly lowered LDL-cholesterol.
“In the non-obese group, spirulina supplementation showed a significant lowering effect on plasma concentration of total cholesterol and LDL-cholesterol, while no changes were observed in the placebo group.”
Quote in the paperSubstantial claim - Findingown data
In obese Korean elderly, spirulina supplementation did not significantly change plasma cholesterol or triglyceride after 4 months.
“However, in the obese group, after 4 months of intervention, no significant changes were observed in the plasma concentrations of cholesterol and triglyceride (Table 2).”
Quote in the paperSubstantial claim - Study design and conductown data
There were no significant differences in age, anthropometry data, and blood pressure at baseline between spirulina and placebo groups for either BMI group.
“As shown in Table 1, there were no significant differences in age, anthropometry data, and blood pressure in baseline characteristics between spirulina and placebo groups for either BMI group (Table 1).”
Quote in the paperSubstantial claim - Interpretationreasoning
Obese people require different doses of spirulina supplementation compared with the non-obese group.
“It is clear that obese people require different doses of spirulina supplementation compared with the non-obese group.”
Quote in the paperSubstantial claim - Interpretationown data
The health promotion effect of spirulina supplement can be reduced in obese people.
“Also, in this study, lipid-lowering effect and antioxidant capacity appeared to be low in the obese group, indicating that health promotion effect of spirulina supplement can be reduced in obese people.”
Quote in the paperSubstantial claim- The authors state this as an assumption: Obesity itself may impair immunity and can also induce oxidative stress.
- Interpretationown data
Obesity may influence the effect of spirulina supplementation.
“Our results suggest that obesity may influence the effect of spirulina supplementation.”
Quote in the paperSubstantial claim - Interpretationown data
The intake effect of functional food differs according to personal characteristics including obesity.
“The result of this study shows that intake effect of functional food differs according to personal characteristics including obesity”
Quote in the paperSubstantial claim - Interpretationown data
The intervention effect of spirulina differs according to obesity in Korean elderly.
“From these results, we could confirm that the intervention effect of spirulina differs according to obesity.”
- Also stated in: § CONCLUSIONS · boosted
“These results demonstrated that blood lipid lowering and immune and antioxidant improving response for spirulina supplement was affected by obesity in Korean elderly.”
Quote in the paperSubstantial claim - Also stated in: § CONCLUSIONS · boosted
- The quote only partly states this claim. 1
- May combine two claims. 10
- Classified as probably not a substantial claim. 12
The quote only partly states this claim.
Findingown dataThe significant time-by-treatment intervention for TBARS was observed only in the non-obese group.
“A significant time-by-treatment intervention for TBARS was observed in the non-obese group (P < 0.05).”
Quote in the paperSubstantial claimMay combine two claims.
Study design and conductown dataIn the obese group, total energy intake and carbohydrate intake were higher in the placebo group compared with the spirulina group at baseline (P < 0.05).
“In the obese group, total energy intake and carbohydrate intake were higher in the placebo group compared with the spirulina group (P < 0.05).”
Quote in the paperNot a substantial claimMay combine two claims.
PremisecitationSpirulina supplementation had favorable effects on lipid profiles, immune functions, and antioxidant capacity in healthy Korean elderly in a previous study.
“We have already reported on the effect of spirulina for lipid lowering, immune response, and antioxidant capacity in Korean elderly [14].”
- Also stated in: § BACKGROUND/OBJECTIVES · plain
“We have previously shown that spirulina had favorable effects on lipid profiles, immune functions, and antioxidant capacity in healthy Korean elderly.”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [14] Park, 2008, Ann Nutr Metab source
Not checked in the free run.
- Also stated in: § BACKGROUND/OBJECTIVES · plain
Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.
Study design and conductown dataThe study protocol was approved by an institutional review board, and all subjects gave written informed consent.
“The protocol was approved by the Institutional Review Board of Ewha Womans University Medical Center (ECT 109-02-01). All subjects gave written informed consent before beginning the study and were free to withdraw from the study at any time without obligation.”
Quote in the paperNot a substantial claimMay combine two claims.
Study design and conductown dataIn the non-obese group, fasting blood sugar and triglyceride level were higher in the spirulina group compared with the placebo group at baseline (P < 0.05).
“In the non-obese group, fasting blood sugar and triglyceride level were higher in the spirulina group compared with the placebo group (P < 0.05).”
Quote in the paperNot a substantial claimClassified as probably not a substantial claim. May combine two claims.
Study design and conductown dataThe study was randomized, double-blind, and placebo-controlled.
“In this double-blind, placebo-controlled protocol, the subjects were randomly assigned in a blinded fashion to receive either spirulina or placebo for 4 months.”
Quote in the paperSubstantial claimMay combine two claims.
PremisecitationObesity is associated with systemic inflammation and impaired immunity.
“Obesity is associated with systemic inflammation and impaired immunity.”
Quote in the paperSubstantial claim0 of 3 sources checkedProbably not a substantial claim: may not pass S3 (load-bearing).
PremisecitationOverweight and obese adult humans have a defective cellular immune response to pandemic H1N1 influenza A virus.
“Paich et al. [34] reported that overweight and obese adult humans have a defective cellular immune response to pandemic H1N1 influenza A virus.”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [34] Paich, 2013, Obesity (Silver Spring) source
Not checked in the free run.
May combine two claims.
PremisecitationPlasma IL-2 concentration decreases with aging, so raising plasma IL-2 levels is important for proper immune regulation in elderly people.
“As the concentration of plasma IL-2 decreases according to aging, raising plasma IL-2 levels is important for proper immune regulation in elderly people [37].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [37] Rabinowich, 1985, Mech Ageing Dev source
Not checked in the free run.
Probably not a substantial claim: may not pass S3 (load-bearing).
InterpretationreasoningOther dietary supplements may require different doses in obese people.
“It is not only for spirulina, but other dietary supplements may require different doses in obese people.”
Quote in the paperNot a substantial claimProbably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.
PremisecitationObesity is an important factor correlating with decreased vaccine-induced immune response, which may affect adaptive immune responses.
“Scott et al. [35] reported that one important factor correlating with decreased vaccine-induced immune response is obesity, which may affect adaptive immune responses.”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [35] Scott, 2015, Diabetes Obes Metab source
Not checked in the free run.
Probably not a substantial claim: may not pass S3 (load-bearing).
PremisecitationIn obese individuals, visceral adipose tissue is the major source of proinflammatory cytokines.
“In obese individuals, visceral adipose tissue is the major source of proinflammatory cytokines [30].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [30] Magrone, 2015, Front Immunol source
Not checked in the free run.
Probably not a substantial claim: may not pass S3 (load-bearing).
PremisecitationAdipocytes secrete TNF-α, IL-6, IL-12, IL-1β, and MCP-1 in large amounts.
“Osborn et al. [31] reported that adipocytes secrete TNF-α, IL-6, IL-12, IL-1β, and monocyte chemotactic protein-1(MCP-1) in large amounts.”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [31] Osborn, 2012, Nat Med source
Not checked in the free run.
Probably not a substantial claim: may not pass S3 (load-bearing).
PremisecitationIn a study of treatment response in obese subjects, obesity may be a predictor of poor antibody response.
“In a study of treatment response in obese subjects, Weber et al. [29] first reported that obesity may be a predictor of poor antibody response.”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [29] Weber, 1985, JAMA source
Not checked in the free run.
Probably not a substantial claim: may not pass S3 (load-bearing).
Premisecitationβ-cell function tended to be greater following L-carnitine supplement in the lean group only.
“In fact, β-cell function tended to be greater following L-carnitine supplement in the lean group only [38].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [38] Galloway, 2011, Amino Acids source
Not checked in the free run.
Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.
PremisecitationObesity can induce oxidative stress in adipocytes via production of reactive oxygen species by mitochondria, which can be increased in response to a high-fat diet.
“Obesity can also induce oxidative stress in adipocytes via production of reactive oxygen species (ROS) by mitochondria which can be increased in response to a high-fat diet [3233].”
Quote in the paperNot a substantial claim0 of 2 sources checkedProbably not a substantial claim: may not pass S3 (load-bearing).
PremisecitationCurcuminoids supplementation resulted in no significant change in serum concentrations of oxidative markers anti-Hsp27 and anti-oxidized LDL in obese individuals.
“And curcuminoids supplementation, which have potentially important functional qualities including anti-inflammatory and antioxidant properties, resulted in no significant change in serum concentrations of oxidative markers anti-Hsp27 and anti-oxidized LDL in obese individuals [39].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [39] Sahebkar, 2013, Phytother Res source
Not checked in the free run.
Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.
PremisecitationIL-2 is an anti-inflammatory cytokine and an essential regulator of chronic inflammatory responses.
“IL-2, an anti-inflammatory cytokine, is an essential regulator of chronic inflammatory responses [36].”
Quote in the paperNot a substantial claim0 of 1 sources checked- cites [36] Adler, 1989, Geriatrics
Not checked in the free run.
The paper relies on this without support.
Few studies have examined the effect of food supplementation by BMI.
“Few studies have examined the effect of food supplementation by BMI.”
The authors state this as an assumption.
Obesity itself may impair immunity and can also induce oxidative stress.
“It can be assumed, as described above, obesity itself may impair immunity and can also induce oxidative stress.”
Claims other papers make about this one
Each is checked against this paper’s own text: does it say what the citing paper says it does?
The consumption of spirulina leads to a decrease in blood lipid levels and an improvement in the immune and antioxidant response in obese people.
“The consumption of spirulina leads to a decrease in blood lipid levels and an improvement in the immune and antioxidant response in obese people [114].”
From Application of Arthrospira platensis for Medicinal Purposes and the Food Industry: A Review of the Literature (2023) · cites this paper as [114]
The Results report significant cholesterol reductions in the non-obese group but no significant cholesterol or triglyceride changes in the obese group. The Discussion likewise says the LDL-cholesterol reduction was not observed in obese subjects, while their immune and antioxidant responses were smaller. The claim incorrectly attributes the benefits to obese people. (LLM, conf=0.90)
Checked by a reasoning model — may be wrong.
Experimental — accuracy not yet measuredThe effects of Spirulina on cytokines and on lymphocytes' proliferation depend on age, gender, and body weight differences.
“The effects on cytokines and on lymphocytes' proliferation depend on age, gender, and body weight differences.”
From Antioxidant, Immunomodulating, and Microbial‐Modulating Activities of the Sustainable and Ecofriendly <i>Spirulina</i> (2017) · cites this paper as [98]
The antioxidant effect of Spirulina is confirmed by intervention studies.
“Although the antioxidant effect of Spirulina is confirmed by the intervention studies”
From Antioxidant, Immunomodulating, and Microbial‐Modulating Activities of the Sustainable and Ecofriendly <i>Spirulina</i> (2017) · cites this paper as [98]
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
Each contradiction between two passages listed here was confirmed by an independent check.
Supplementation duration is reported as both 12 and 16 weeks
MinorThe abstract says subjects received spirulina or placebo for 12 weeks, while the methods specify 16 consecutive weeks.
“subjects were fed either placebo or spirulina daily, at 8 g for 12 weeks.”
“The subjects were instructed to consume spirulina or placebo at home, 8 g per day, for 16 consecutive weeks.”
Abstract denies an obese-group effect that the results report
MinorThe abstract says the listed effects, including increased IL-2, were not observed in the obese group. The results state that IL-2 significantly increased in that group after spirulina supplementation.
“In the non-obese group, spirulina supplementation showed a significant lowering effect on plasma concentration of total cholesterol and LDL-cholesterol, a significant increase in interleukin (IL)-2 concentration (P < 0.01) and a significant increment (P < 0.05) in IL-2/IL-6 ratio, and a significant increase in total antioxidant status level and a significant decrease in thiobarbituric acid reactive substances level. However, these effects were not observed in the obese group.”
“In the obese group, like in non-obese subjects, the level of IL-2 was significantly increased after 4 months of spirulina supplementation.”
The citation lists haven’t been fetched yet
References 39 · Cited by 34
Research works printed but not linked: 6
- Bhavisha, 2010, J Pharm Res, 3, 1726
- Serban, Clin Nutr
- Korean Nutrition Society, 2006, CAN-Pro: computer aided nutritional analysis program
- Lauer, 1988, Pediatrics, 82, 309
- Yang, 2014, J Nutrit Health Food Sci, 1
- Adler, 1989, Geriatrics, 44, 7
- Authors
- Park, H.-J., & Lee, H.-S.
- Affiliations
- Kookmin University (KR)
- Dongseo University (KR)
- Corresponding author
- Lee, Hyun-Sook
- Venue
- Nutrition Research and Practice
- Published
- 2016
- Volume
- 10
- Issue
- 4
- Pages
- 418
- ISSN
- 1976-1457 (ISSN-L)
- 2005-6168
- PMC
- PMC4958645
- OpenAlex
- W2338736352
- Semantic Scholar
- e866fe92460603107983965dca121a138101f1dd
- Cited by
- 34
- References
- 39
- Citations by year
- 2026: 3 · 2025: 4 · 2024: 5 · 2023: 2 · 2022: 3 · 2021: 7 · 2020: 3 · 2019: 2 · 2018: 2 · 2017: 2 · 2016: 1
- FWCI
- 3.36
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- Locations
- Nutrition Research and Practice (publishedVersion, cc-by-nc)
- PubMed Central (publishedVersion, cc-by-nc)
- PubMed (publishedVersion)
- Funders
- Korean Research Foundation (R04-2003-000-10119-0)
- ES biotech
- Topics
- Life Sciences › Agricultural and Biological Sciences › Aquatic Science › Seaweed-derived Bioactive Compounds
- Health Sciences › Nursing › Nutrition and Dietetics › Fatty Acid Research and Health
- Physical Sciences › Energy › Renewable Energy, Sustainability and the Environment › Algal biology and biofuel production
- Keywords
- Spirulina, dietary supplementation, obesity, older adults, hypolipidemic effect, immunomodulation, antioxidant capacity, interleukin-2, interleukin-6, total antioxidant status, oxidative stress, LDL cholesterol, total cholesterol, Korean older adults
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