Medicines Q&As
Q&A 430.1
What is raspberry ketone, and does it help with weight loss?
Prepared by UK Medicines Information (UKMi) pharmacists for NHS healthcare professionals
Before using this Q&A, read the disclaimer at www.ukmi.nhs.uk/activities/medicinesQAs/default.asp
Date prepared: 2nd January 2014
Background
Raspberry ketone has recently become popular as a weight loss aid, due to celebrity endorsements
and media features. It is widely available online, and is being heavily advertised through social media
and other channels, making it an enticing product for people wishing to lose weight.1,2
Raspberry ketone is contained within the berries of the raspberry plant.3 It is the major aromatic
compound of raspberries, giving them their flavour and aroma. It is widely used as a flavouring in the
food industry.1,4
Despite the seemingly impressive claims on promotional websites, evidence for the efficacy of
raspberry ketones is currently very limited, as detailed in this Medicines Q&A.
Answer
Mechanism of action
The use of raspberry ketone as a weight loss aid stems from its chemical similarity to capsaicin and
synephrine. It has been theorised that raspberry ketones may work by increasing lipid metabolism
ands increasing norepinephrine-induced lipolysis and thermogenesis. However, this is based on
animal model studies only, and it is currently unknown if these actions also occur in humans.1
Evidence
There are no studies of the effects of raspberry ketone in humans reported in the medical literature.
Even evidence of its efficacy in animals is limited to rodent studies only, and only one of these
measures body weight.
The first study was published in 2005. This study was performed on mice, which were split into five
groups (n=6 in each group).5 One group was fed a normal diet, one was fed a high fat diet, whilst the
other three groups were fed a high fat diet with either a 0.5, 1, or 2% raspberry ketone component.
There were significant differences in weight, but due to poor reporting and trial quality, no conclusions
can be drawn.5
An in vitro study on mouse 3T3-L1 adipose cells showed that raspberry ketone increased lipolysis in
this cell line. The clinical significance of these actions, and how this can contribute to weight loss,
remains unknown.6
A study in rats set out to determine the effects of raspberry ketone against steatohepatitis caused by
a high fat diet7. Again, this was a short term study of 8 weeks duration, after which the rats were
sacrificed. Unfortunately, the weight of the rats was not measured in this study, and again very small
numbers were used in each experimental group (n=8). The results of this studied showed that serum
and hepatic lipid levels were reduced in the 2% raspberry ketone group, but applicability to humans
remains unknown.7
Available through NICE Evidence Search at www.evidence.nhs.uk
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Medicines Q&As
Safety
Due to the complete lack of human clinical trial evidence, there is insufficient reliable information
about the safety of raspberry ketone in humans. It should be avoided by pregnant and lactating
women1.
Theoretically, raspberry ketone may have a side effect profile similar to stimulant drugs. 1 One case
report describes a 43 year old man with no PMH, who suffered from insomnia, palpitations, and
jitteriness due to the ingestion of a raspberry ketone product.2
Another case report describes a patient who was using a raspberry ketone supplement along with a
range of other herbal medicines. She underwent an unapproved weight loss therapy called
Lipodissolve, and subsequently went into multi-organ failure. The role of raspberry ketone in this
adverse reaction remains unknown.8
There are no licensed raspberry ketone products available, nor are there any products that are
registered under the MHRA’s Traditional Herbal Registration scheme. Products may be of variable
quality, and contamination may be an issue. 9
Adverse reactions to raspberry ketone should be reported via the MHRA’s Yellow Card Scheme.10
Summary



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There are currently no reliable data to justify the claims being made about raspberry ketone by
online retailers.
There is some evidence from animal model studies which suggests that raspberry ketone may
have some protective effects against high fat diets. However, this is currently too limited to draw
any conclusions from.
There is no information about safety of raspberry ketone, but there are some indicators that it may
cause adverse reactions.
Patients wishing to lose weight should follow a healthy, balanced diet and exercise regime.11
Limitations
This Medicines Q&A assesses only the evidence for oral raspberry ketone as a weight loss aid. It
does not look at evidence for other uses.
Quality Assurance
Prepared by
Hayley Johnson, Regional Drug & Therapeutics Centre, Newcastle upon Tyne.
Date Prepared
2nd January 2014
Checked by
Nancy Kane, Regional Drug & Therapeutics Centre, Newcastle upon Tyne.
Date of check
7th January 2014
Search strategy
Embase:
(Raspberry AND ketone).ti.ab
Medline:
(Raspberry AND ketone).ti.ab
Available through NICE Evidence Search at www.evidence.nhs.uk
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Medicines Q&As
Natural Medicines Comprehensive Database
Herbal Medicines
Micromedex
General Google search
References
1
Raspberry Ketone Monograph. In: Natural Medicines Comprehensive Database. Accessed via
www.naturaldatabase.com on 2nd January 2014. Last updated 30/03/2013.
2 Takematsu M, Smith S, Hoffman R et al. Berries that weren’t that sweet after all- a case of raspberry
ketone intoxication (Meeting abstract) Clinical Toxicology 22013; 51/4(284): 1556-3650
3 Raspberry In: Herbal Medicines. [online] London: Pharmaceutical Press.
http://www.medicinescomplete.com/ [Accessed on 2nd January 2014]
4 Hicks, R. Raspberry ketones. Boots WebMD. Accessed via
http://www.webmd.boots.com/diet/raspberry-ketones on 3rd January 2013. Last reviewed 25th
February 2013
5 Morimoto C, Satoh Y, Hara M et al. Anti-obese action of raspberry ketone. Life Sciences 2005; 77:
194-204
6 Park K. Raspberry ketone increases both lipolysis and fatty acid oxidation in 3T3-L1 adipocytes.
Planta Medica 2010; 76(15): 1654-1658
7 Wang L, Meng X, and Zhang F. Raspberry ketone protects rats fed high-fat diets against
nonalcoholic steatohepatitis 2012: 15(5); 495-503
8 Libby B, Ruha A-M, Raschke R et al. Multisystem organ failure following lipodissolve injections.
Clinical Toxicology 2012: 50(7); 683-684
9 Medicines Healthcare Products Regulatory Agency. Herbal Medicines: Advice for customers.
Accessed via
http://www.mhra.gov.uk/Safetyinformation/Generalsafetyinformationandadvice/Herbalmedicines/index
.htm on 3rd January 2014
10 Medicines Healthcare Products Regulatory Agency. Reporting problems with herbal medicines.
Accessed via
http://www.mhra.gov.uk/Safetyinformation/Generalsafetyinformationandadvice/Herbalmedicines/Repo
rtingproblemswithherbalmedicines/index.htm on 3rd January 2014
11 Obesity: Clinical Knowledge Summaries Guidelines. Accessed via
http://cks.nice.org.uk/obesity#!scenariorecommendation:11 on 3rd January 2014. Last revised
October 2012
Available through NICE Evidence Search at www.evidence.nhs.uk
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