Saturday, December 24, 2011

The smell of Christmas

How does Christmas smell like? 

Like cinnamon! So say studies by European scientists  [1-3]. And even though the smell of cinnamon is described as "pungent" (besides "warm", 'sweet", and "spicy"), it fires up our brains, evoking a joyful Christmas mood and making us more generous. 

Cinnamon is classified as a stimulant. Smelling and tasting cinnamon could enhance attention and virtual recognition memory [4], at least in comparison to smells of peppermint, jasmine or cherries. In addition to its many healthy properties - like fighting E.coli in unpasteurized juices, lowering concentration of  fasting glucose, triglycerides, and total cholesterol - Cinnamon can make you feel fuller for longer [5]. So for those of us hoping to lose some weight - a cinnamon-flavored floss would be a good replacement for a Christmas desert.

Aggregate correlations - aka experience of the crowds analyzed in Aurametrix - tell many good things about Cinnamon. For example, that it led to less severe joint pain and helped with bad breath. Although - in higher concentrations - it was the reason of a yellowish skin.

Unfortunately for those with digestive problems, other Christmas-flavored foods seemed to have more side effects. Aurametrix correlations for Apple told that exceeding sensitivity thresholds could lead to gas, fecal and musty smell (was this why an apple a day kept the doctor away?). Too much orange was associated with bloating, indigestion and yellow stool. Pumpkin, on the other hand, lead to slightly better flavored gas!

With more daily observations entered by the users, Aurametrix will make more correlations between wellbeing and food flavors. But for now -

Merry Christmas! And let's smell some cinnamon!


1. Seo HS, Buschhüter D, & Hummel T (2009). Odor attributes change in relation to the time of the year. Cinnamon odor is more familiar and pleasant during Christmas season than summertime. Appetite, 53 (2), 222-5 PMID: 19576937

2. Martin Lindström, Philip Kotler. Brand Sense: Sensory Secrets Behind the Stuff We Buy. Simon and Schuster, Feb 2, 2010

3. Idle JR. Christmas gingerbread (Lebkuchen) and Christmas cheer--review of the potential role of mood elevating amphetamine-like compounds formed in vivo and in furno. Prague.Med Rep. 2005;106(1):27-38.

4. Phillip Zoladz.  2003-2004 Allyn & Bacon Award Abstracts. Impact of the Chemical Senses on Augmenting Memory, Attention, Reaction Time, Problem Solving, and Response Variability: The Differential Role of Retronasal Versus Orthonasal Odorant Administration

5. Hlebowicz, J., Hlebowicz, A., Lindstedt, S., Bjorgell, O., Hoglund, P., Holst, J., Darwiche, G., & Almer, L. (2009). Effects of 1 and 3 g cinnamon on gastric emptying, satiety, and postprandial blood glucose, insulin, glucose-dependent insulinotropic polypeptide, glucagon-like peptide 1, and ghrelin concentrations in healthy subjects American Journal of Clinical Nutrition, 89 (3), 815-821 DOI: 10.3945/ajcn.2008.26807

6. Khan A, Safdar M, Ali Khan MM, Khattak KN, Anderson RA. Cinnamon improves glucose and lipids of people with type 2 diabetes. Diabetes Care 2003;26:3215–8.

7. Catherine Ulbricht, Erica Seamon, Regina C. Windsor, Nicole Armbruester, J. Kathryn Bryan, Dawn Costa, Nicole Giese, Joerg Gruenwald, Ramon Iovin, Richard Isaac, Jill M. Grimes Serrano, Shaina Tanguay-Colucci, Wendy Weissner, Heeja Yoon, and Jie Zhang. An Evidence-Based Systematic Review of Cinnamon (Cinnamomum spp.) by the Natural Standard Research Collaboration.  Journal of Dietary Supplements, December 2011, Vol. 8, No. 4 : Pages 378-454 (doi: 10.3109/19390211.2011.627783)

Monday, December 5, 2011

The Road to Ammonia

Why do I smell like Ammonia? This question, in thousands of variations, has been asked over and over again at every major question/answer site, especially teen, bodybuilding and athletic forums.

The Internet provides plenty of opinions.

Medical sites talk about diseases like chronic kidney failure, hepatic cirrhosis or H. pylori infection. Fitness sites recommend drinking more water, reevaluating protein sources and eating more carbohydrates.
What are these diet-odor links? And what's the Science? Ammonia may be formed during the alkaline hydrolysis and deamidation of proteins - by our own metabolism and the metabolism of microbes that call us home. If our kidneys can't handle the load of nitrogen, it's excreted as ammonia in sweat. Excretion increases 10 times as temperature goes from 70 to 100 Fahrenheit.

Aurametrix is a breakthrough analysis tool that correlates users' actions and reactions based on what information they enter into the system. Preliminary correlations in the Aurametrix knowledge base show exactly what's expected: excess protein does lead to ammonia-like odor.

But wait a minute - does it say the same about excess fat?

An  example provided by one of our users is very interesting. The user logged a few foods he thought were contributing to odor. These were different odors according to the user - ranging from "Ammonia-like" to "Fishy", sharp, cloying and stale. Aurametrix, however, recognized that all these odors described by the user may be related to nitrogen-containing compounds.  When these three data points were analyzed along with four foods that the user did not associate with any odors, Aurametrix displayed only one result:

Based on your Aura entries, the following may be contributing to "Ammoniacal odor" in a 3 hour timeframe:

Hexadecanoic acid  - commonly known as Palmitic acid - is one of the most common saturated fatty acids in the Western diet. Palm oil and coconut oil contain especially high levels of this acid. What effect does this acid have on metabolism? It down-regulates glycose metabolism and protein metabolism, affecting Calcium or mRNA binding proteins [1]. So there may very well be a connection!

Want to connect the dots to your own health and wellbeing and see what you have in common with others?

Write to:


Hovsepyan, M., Sargsyan, E., & Bergsten, P. (2010). Palmitate-induced changes in protein expression of insulin secreting INS-1E cells Journal of Proteomics, 73 (6), 1148-1155 DOI: 10.1016/j.jprot.2010.01.012

Trabue S, Kerr B, Bearson B, Ziemer C. Swine odor analyzed by odor panels and chemical techniques. J Environ Qual. 2011 Sep-Oct;40(5):1510-20.

Ito, Shigeji; Kohli, Yoshihiro; Kato, Takuji; Abe, Yoshimichi; Ueda, Takashi
Significance of ammonia produced by Helicobacter pylori. European Journal of Gastroenterology & Hepatology. 6(2):167-174, February 1994.

Qiu, Y.T., Smallegange, R.C., Van Loon, J.J.A., Takken, W. 2011 Behavioural responses of Anopheles gambiae sensu stricto to components of human breath, sweat and urine depend on mixture composition and concentration. Medical and Veterinary Entomology 25 (3), pp. 247-255

Enrique Wolpert, M.D., Sidney F. Phillips, M.D., and W. H. J. Summerskill, D.M. Ammonia Production in the Human Colon — Effects of Cleansing, Neomycin and Acetohydroxamic Acid N Engl J Med 1970; 283:159-164

V Bhatia, R Singh, S K Acharya Liver: Predictive value of arterial ammonia for complications and outcome in acute liver failure. Gut 2006;55:98-104 Published Online First: 15 July 2005 doi:10.1136/gut.2004.061754

Consolazio, C.F., Nelson, R.A., Matoush, L.O., Canham, J.E. Nitrogen excretion in sweat and its relation to nitrogen balance requirements. J Nutr. 1963 Apr; 79:399-406.

Ammonia in personal care products:
After Bite ointments
Hair dyes

Ammonia in household products:
Ammonia Removing Products
Glass Cleaners
Kitchen Cleaners

Saturday, November 5, 2011

What's that fatty odor?

Body odor is closely associated with diet. Deciphering the chemistry of human odor is not an easy task - only about 5% of odorous molecules are usually recovered from collection containers, and not all of the molecules are identified in complex spectra. Volatile fatty acids, alcohols, and aromatic ring compounds comprise a substantial fraction of smelly molecules, yet very little is known about the origin and factors controlling their production in humans. Fortunately for some (and not so fortunately for others), the human nose can capture and discriminate many smell signatures. Could this discrimination be used to connect the dots between diet and body odor? MEBO Research has just started an anonymous study using the Aurametrix health analysis tool to find out.

Aurametrix's knowledge base provides a wide selection of foods and symptoms, including different types of odors recognizable by the human nose. Participants in the study have been recording some of their food intake and activities on days when their symptoms are better or worse than average, entering items they suspect might be contributing to or alleviating their body odor on those days. The tool's analysis engine then lets them explore all the possible cause-effect relationships. In addition, Aurametrix performs automated analyses across the entire user community and displays cumulative results as "aggregate correlations." The figure on the right is an excerpt from these results.

Although the study has only just begun, the preliminary results already look very interesting. One example is fatty odor. Aurametrix linked several dietary chemicals to unpleasant "fatty odor" emanating from skin based on Aura entries of several participants. The top chemicals so far are:  Vitamin K1 (phylloquinone), Octadecanoic acid, FODMAPs, Beta-carotene,  Carbohydrates and Monosaccharides. Another interesting result (although there were fewer observations) is that Vitamin B12 obtained from diet seemed to help prevent fatty body odor.
  • Could Vitamin K1 really contribute to "fatty" odor?  Could 6 observations derived from different users' Auras be just a coincidence? Vitamin K is proposed to increase production of alkaline phosphatase in intestines. This enzyme produces a number of different substances, some of which have a peculiar sweetish smell.  Chlorophyll, usually recommended to combat body odor and supposedly makes odor "sweeter," is an excellent source of vitamin K1. And so is Asparagus that gives urine a disagreeable odor.
  • Octadecanoic (Stearic) acid was also linked to fatty odor in 6 observations. This saturated fatty acid is most abundant in animal fats and cocoa butter, and also in nuts and seeds (peanuts, flax), cheese, cookies and candies. Its smell is fairly mild, yet can be detected by the human nose (Bolton and Halpern, 2010). Besides, it slowly converts in the liver to heart-healthy oleic acid which has a faintly fatty odor with a hint of dead insects. It could also metabolize into other compounds and incorporate into liver lipids or follow alternative routes.
  • FODMAPs, highly fermentable but poorly absorbed short-chain carbohydrates and polyols, were found to be an important dietary factor contributing to gastrointestinal symptoms. Perhaps FODMAPs, carbohydrates and monosacharides in particular could also contribute to odor in the absence of GI discomfort?
  • Beta-carotene is another heart-healthy chemical with anticancerous properties important in human nutrition as a source of Vitamin A. Tobacco, tea, many spices and flowers owe their flavors to chemicals metabolized from beta-carotene. One of such chemicals is warm and woody beta-Ionone that smells of blackberry at lower concentrations and fatty-cheesy at higher concentrations.

The chemistry of odors and their origins is undoubtedly very complex. Yet, these preliminary results show that together we may find the answers to many health-related questions. With more participants, we'll soon connect the dots between diet and body odor. Want to participate? Write to:


Bolton B, & Halpern BP (2010). Orthonasal and retronasal but not oral-cavity-only discrimination of vapor-phase fatty acids. Chemical senses, 35 (3), 229-38 PMID: 20100787

Dunkel M, Schmidt U, Struck S, Berger L, Gruening B, Hossbach J, Jaeger IS, Effmert U, Piechulla B, Eriksson R, Knudsen J, & Preissner R (2009). SuperScent--a database of flavors and scents. Nucleic acids research, 37 (Database issue) PMID: 18931377

Wednesday, February 2, 2011

Colonoscopy for everyone! ..or Gonna Buy Me A Dog

New research from Japan brings good news: dogs can be almost as accurate as a colonoscopy exam.
In patients with colorectal cancer (CRC) and controls, the sensitivity of canine scent detection of breath samples compared with conventional diagnosis by colonoscopy was 0.91 and the specificity was 0.99.
The sensitivity of canine scent detection of watery stool samples was 0.97 and the specificity was 0.99.
The accuracy of canine scent detection was high even for early cancer. Canine scent detection was not confounded by current smoking, benign colorectal disease or inflammatory disease.  
As simple as that: exhaling 100-200 ml into a breath sampling bag and storing it in a Ziploc bag at 4°C until a trained dog has a change to sniff it can be enough for diagnostics. Just one breath sample! And it was almost as good as a watery stool sample obtained during colonoscopy or this joyous examination itself.

There have been many research studies that dogs, rats and even moth can detect scents pertaining to human disease. Ordinary household dogs can be trained to distinguish breath odors (McCulloch et al 2006). For some cancers, sensitivity can be as high as 100% (Horvath et al 2008).

Unfortunately, sophisticated mass-spectrometry, gas chromatography and software tools interpreting the signals are still not as good as our four-legged friends that are never getting lost in the noise of disease-unrelated flavors.
But we are getting better in identifying specific chemicals responsible for various conditions - from alkanes  - such as pentane in breath of IBD patients and polystyrene foam or aromatic components of petroleum in cancer breath to blends of fatty acids like oleic and linoleic acids forming the smell of death.

Perhaps pet rats will find their use as pocket doctors before men-made sensors are developed to cope with infections, medical conditions, even fear and anxiety that also have a distinctive odor signature. In any case, Dr. Sonoda and his colleagues bring us a reassuring word that not every frequent visitor to the GI doctor's office will have to experience the joys of a colonoscopy.

Sonoda H, Kohnoe S, Yamazato T, Satoh Y, Morizono G, Shikata K, Morita M, Watanabe A, Morita M, Kakeji Y, Inoue F, & Maehara Y (2011). Colorectal cancer screening with odour material by canine scent detection. Gut PMID: 21282130

Other published literature on olfactory signatures in gastrointestinal disease:

Cheu HW, Brown DR, Rowe MI (1989) Breath hydrogen excretion as a screening test for the early diagnosis of necrotizing enterocolitis. Am J Dis Child 1989;143:156–9.

Pelli MA, Trovarelli G,, Capodicasa E, Breath alkanes determination in ulcerative colitis and Crohn's disease. Dis Colon Rectum 1999;42:71–6.

Pelton NS, Tivey DR, Howarth GS, A novel breath test for the non-invasive assessment of small intestinal mucosal injury following methotrexate administration in the rat. Scand J Gastroenterol 2004;9:1015–16.

Tibble JA, Sigthorsson G, Foster R, Use of surrogate markers of inflammation and Rome criteria to distinguish organic from nonorganic intestinal disease. Gastroenterology 2002;123:450–60.