Evidence supporting the use of: Synephrine
For the body system: Sympathetic Nervous System
Synopsis
Source of validity: Scientific
Rating (out of 5): 2
Synephrine is a naturally occurring alkaloid found primarily in the bitter orange (Citrus aurantium) plant. It is structurally similar to ephedrine and is believed to exert sympathomimetic effects, meaning it can stimulate the sympathetic nervous system (SNS). Synephrine acts primarily as an agonist at adrenergic receptors, particularly the β3-adrenergic receptor, which can lead to increased thermogenesis, lipolysis, and mild increases in metabolic rate. These properties have led to its inclusion in dietary supplements marketed for weight loss, energy enhancement, and athletic performance.
There is some scientific evidence supporting synephrine’s action on the SNS. Clinical studies have documented modest increases in metabolic rate, heart rate, and blood pressure after synephrine administration. However, these effects are generally less pronounced than those of ephedrine. According to a 2012 review published in Phytotherapy Research, human studies with synephrine-containing products have reported small but statistically significant elevations in energy expenditure and fat oxidation, which are consistent with mild sympathetic activation.
Despite these findings, the overall strength of the evidence is limited by small sample sizes, short study durations, and variability in product formulations. Safety concerns have also been raised, particularly regarding cardiovascular risks when synephrine is combined with other stimulants. In summary, while there is some scientific validation for synephrine’s ability to support or stimulate the sympathetic nervous system, the evidence is modest and not robust.
Other ingredients that support Sympathetic Nervous System
1,3,7-Trimethylpurine-2,6-dione7,8-Dihydroxyflavone
Acetyl L-carnitine
Acetyl-L-Tyrosine
Adrenergic amines
ashwagandha
Bacopa
bacoside
basil
bergamot
beta caryophyllene
brahmi
bасора
caffeine
capsaicinoids
cardamom
catecholamine
cayenne pepper
citrus sinensis (proprietary)
cola nut
Convolvulus pluricaulis
cortisol
cowage seed
electrolytes blend (proprietary)
eleuthero
Ephedra
ephedrine
gastrodia
ginkgo biloba
Ginsenosides
glucose
guarana
Guaranine
guayusa
herbal blend (proprietary)
Higenamine
Jatamansi
jiaogulan
jujube
kanna
kola nut
kudzu
L-taurine
L-theanine
l-tyrosine
lavender
lemongrass
licorice root
lion's mane
lotus seed
magnesium
magnolia
Methylxanthine
Muira puama
Mulungu
omega-3 fatty acids
paraxanthine
passionflower
phytocannabinoids
relora® (proprietary)
Rhodiola
robusta coffee
Rosarin
rosavins
Salidroside
salt
Shankhpushpi
skullcap
Synephrine
Szechuan lovage
Tagara
Teacrine
Theacrine
vitamin B
whole adrenal glandular
Withanolides
Xanthine
Yarrow
Yohimbe
Yohimbine
