If you smell grapefruit or lemon, your fat cells release their contents more easily into the bloodstream. Researchers at Niigata University and Osaka University discovered this when they did experiments with rats. Aromatherapy using grapefruit and lemon oil may increase the amount of fat you can lose on a weight-loss diet.
Aromatherapy works. The effects of exposure to scents are modest, but researchers have shown under laboratory conditions that test subjects who smell lavender have an increased feeling of wellbeing, are more relaxed and make fewer mistakes when they have to solve mathematical puzzles. [Int J Neurosci. 1998 Dec; 96(3-4): 217-24.] The scent of rosemary on the other hand makes subjects feel more awake and more alert. Rosemary helped test subjects to solve puzzles more quickly, but had no influence on error rate.
The effects of exposure to scents can also be seen by measuring electrical activity in the brain. And it was this that got the Japanese researchers thinking.
Nerve cells run through fat tissues and activation of these nerves might help increase breakdown of fat. If the nerve pathways could send stronger signals to the fat cells, then the latter might release more fatty acids into the bloodstream. Perhaps aromatherapy could create the necessary stimulus, was the researchers’ reasoning.
Nerve cells run through fat tissues and activation of these nerves might help increase breakdown of fat. If the nerve pathways could send stronger signals to the fat cells, then the latter might release more fatty acids into the bloodstream. Perhaps aromatherapy could create the necessary stimulus, was the researchers’ reasoning.
The figure above shows the effect of lemon and grapefruit oil in a 1:100 solution on the number of electrical pulses that travelled along the nerve pathways to the white fat cells in the epididymis. Grapefruit oil was particularly effective.
“It is reasonable to assume that olfactory stimulation with the flavor of the citron group activates sympathetic outflow to the white adipose tissue and facilitates the release of norepinephrine from the nerve terminals, which activates lipolysis and finally suppresses body weight gain”, the researchers conclude. “The effect of the olfactory stimulation with flavors of the citron group on the concentration of fatty acid and glycerol in the blood should be investigated in further study.”
Effect of olfactory stimulation with flavor of grapefruit oil and lemon oil on the activity of sympathetic branch in the white adipose tissue of the epididymis.
Exp Biol Med (Maywood). 2003 Nov;228(10):1190-2.
Niijima A, Nagai K.
Source
Niigata University School of Medicine, Asahimachi-dori, Niigata 951-8510, Japan. anathome@med.niigata-u.ac.jp
Abstract
It has been mentioned in the field of aromatherapy that the fragrance of grapefruit has a refreshing and exciting effect, which suggests an activation of sympathetic nerve activity. It also can be assumed that the activation of sympathetic nerve innervating the white adipose tissue (WAT) facilitates lipolysis, then results in a suppression of body weight gain. This study addressed the effect of olfactory stimulation with the scent of grapefruit oil and lemon oil on the efferent nerve activity in the sympathetic branch of the WAT of the epididymis in the anesthetized rat. The results of the experiments demonstrated that the flavor of the citron group increased sympathetic nerve activity to WAT in anaesthetized rat, which suggests an increase in lipolysis and a suppression in body weight gain.
PMID: 14610259 [PubMed – indexed for MEDLINE]
