I would advocate moderation in just about everything. Ketogenic diets have proven helpful to people with uncontrolled epilepsy and may be of benefit to epileptics in general, to victims of stroke and other forms of brain injury and possibly cancer. They come with other effects that may not be worth the discomfort or unintended risks to healthy people. This includes kidney stones and, in women and girls, amenorrhea. Amenorrhea is associated with bone loss, increasing risk of osteoporosis, and indicates problems in hormone balance. Supplementation with calcium may help with this, but then again, it might not. Physiology can be quite complex, and consumption does not necessarily indicate absorption is occurring. It is quite possible that something that causes hormonal imbalance in women may also cause hormonal imbalance in men. Playing with one’s physiology, when we don’t know the unintended outcomes of such play, may be inadvisable, especially long-term.
I have been a vegetarian for 30 years and an athlete all my life. I have excellent bone density, low blood pressure, low resting heart rate, low fasting blood sugar, excellent blood lipid profile and great strength to body weight ratio. I'm happy and healthy, even though I thoroughly understand I represent but a single data point. I do get a lot of advice from well-meaning friends that I need to eat meat and would be much healthier if I followed a ketogenic diet. Vegetarians, as described in some current diet books, are weak and "skinny-fat". I will leave it at this: The "optimal diet" for one person may not be the "optimal diet" for another, nor the optimal diet for all conditions. Humans are omnivores and physiologically polymorphic and adaptable. This has given us tremendous abilitity to survive in wildly different climes and environments, and has made us such a resilient species. It is also quite possible, that our individual resilience allows our bodies to adjust to dietary and environmental change.
The current state of research indicates no harm though, from short-term ketogenic diets. I have not found much in the way of research on the risks and benefits of long-term ketogenic diets in healthy adults. Anyone who wishes to add a citation, please feel free.
Kossoff, E., Zupec-Kania, B., & Rho, J. (2009). Ketogenic Diets: An Update for Child Neurologists Journal of Child Neurology, 24 (8), 979-988 DOI: 10.1177/0883073809337162
Bergqvist AG, Chee CM, Lutchka L, Rychik J, & Stallings VA (2003). Selenium deficiency associated with cardiomyopathy: a complication of the ketogenic diet. Epilepsia, 44 (4), 618-20 PMID: 12681013
Brinkworth GD, Buckley JD, Noakes M, Clifton PM, & Wilson CJ (2009). Long-term effects of a very low-carbohydrate diet and a low-fat diet on mood and cognitive function. Archives of internal medicine, 169 (20), 1873-80 PMID: 19901139
This site provides articles on health, nutrition and chemical exposures. There is a focus on current research and areas where there is controversy and need for further investigation.
Saturday, January 15, 2011
Friday, January 7, 2011
Role of Hormones, Genes, Hybrid Cars and Environmental Factors in Human Cryptorchidism
Undescended testicles (Cryptorchidism) appear to be of complex origin . . . one of those cases where there are genetic and environmental components, and therefore difficult to figure out. You can consider genetics, exposures to environmental estrogens and anti-androgens and the relations among risk factors. You will not be bored trying to figure this one out. Added to this mix is a previously unconsidered variable: Hybrid Cars.
I teach a course called "Introduction to Research" which is somewhat like boot camp for aspiring academics. I would now only encourage people to go into academia if they are so driven by love or fascination for a subject that they are willing to sacrifice a signifant amount material comfort in its pursuit. I described my 16 year old minivan as dented and rusty, with an interior re-upholstered piece-meal with green fluorescent duct-tape. The starstruck response: a breathless and drawn out "cool . . . " I went on to describe my leaky roof and deceased dishwasher, and received this: "Dr. K, I will come to your house and fix your dishwasher" followed by "and I will drape my body over the hole in your roof next time it rains" from yet another. Undergraduates can be absolutely amazing.
So, to the hybrid part of the cryptorchidism story. The minivan leaks oil, gets not-so-good mileage and I drive about 120 miles a day to commute to the University. This is horrible for the environment, and costs about 1/7th of my income in gasonline alone. It suddenly struck me, during a quiet conversation with a good friend, and sometimes nemesis, that I could get a used Prius and maybe come out ahead financially on the reduction in gas expenditures. "Oh No! I'm Emasculating!" (that wasn't exactly how it was phrased, but you get the point: he has just become cryptorchidic). I only struck up a conversation with him in the first place because he looked like a hippie and a good environmentalist. Just another reminder not to speak to strangers even if they look "nice".
So what's the deal with hybrids and environmentalism that threatens the masculinity of men in Texas? A simple question, that could be answered with a simple "beats the hell out of me" until I started considering bumper stickers:
This is a question that should be posed to an historian, psychologist and/or poli sci person.
Foresta, C., Zuccarello, D., Garolla, A., & Ferlin, A. (2008). Role of Hormones, Genes, and Environment in Human Cryptorchidism Endocrine Reviews, 29 (5), 560-580 DOI: 10.1210/er.2007-0042
I teach a course called "Introduction to Research" which is somewhat like boot camp for aspiring academics. I would now only encourage people to go into academia if they are so driven by love or fascination for a subject that they are willing to sacrifice a signifant amount material comfort in its pursuit. I described my 16 year old minivan as dented and rusty, with an interior re-upholstered piece-meal with green fluorescent duct-tape. The starstruck response: a breathless and drawn out "cool . . . " I went on to describe my leaky roof and deceased dishwasher, and received this: "Dr. K, I will come to your house and fix your dishwasher" followed by "and I will drape my body over the hole in your roof next time it rains" from yet another. Undergraduates can be absolutely amazing.
So, to the hybrid part of the cryptorchidism story. The minivan leaks oil, gets not-so-good mileage and I drive about 120 miles a day to commute to the University. This is horrible for the environment, and costs about 1/7th of my income in gasonline alone. It suddenly struck me, during a quiet conversation with a good friend, and sometimes nemesis, that I could get a used Prius and maybe come out ahead financially on the reduction in gas expenditures. "Oh No! I'm Emasculating!" (that wasn't exactly how it was phrased, but you get the point: he has just become cryptorchidic). I only struck up a conversation with him in the first place because he looked like a hippie and a good environmentalist. Just another reminder not to speak to strangers even if they look "nice".
So what's the deal with hybrids and environmentalism that threatens the masculinity of men in Texas? A simple question, that could be answered with a simple "beats the hell out of me" until I started considering bumper stickers:
This is a question that should be posed to an historian, psychologist and/or poli sci person.
Foresta, C., Zuccarello, D., Garolla, A., & Ferlin, A. (2008). Role of Hormones, Genes, and Environment in Human Cryptorchidism Endocrine Reviews, 29 (5), 560-580 DOI: 10.1210/er.2007-0042
Thursday, January 6, 2011
Hearing, Reading Disabilities and PCB exposures
I found this article very exciting. Serum PCB Concentrations and Cochlear Function in 12-Year-Old Children. by Trnovec et al. 2010, in which they describe associations between hearing function and PCB exposures in Slovakian kids. (In regular terms: PCB exposure in children probably causes hearing deficits). My forebears were deaf, graduated from the American School for the Deaf, were members of Deaf Baseball and Football teams, and from all the old pictures we have, seem to have had absolutely fun and wonderful lives, so I've never really considered Deafness a disability. However, hearing deficits make it hard for children to learn to read, and they do not get the full range of information available to children without hearing deficits. This can be a problem that may put them at a disadvantage in terms of conventional measures of school and life success. See Banai et al. 2009 for some recent interesting work in this area.
Trnovec et al. also observed differences between ears (no, not that some kids heads were filled with Kapok and some weren't) with the left ear showing a stronger deficit than the right. This does lead one to wonder if people are left earred or right-earred and that the same effect might not be seen if they had recruited only right-handed or left-handed children. This is also more complex than it seems because you can be right handed and "goofy footed" i.e. left foot dominant. I am goofy footed, but its only apparent when I'm out surfing.
Here is a link for understanding the systems through which Trnovec are evaluating correlations of PCB exposure with hearing. http://www.est-med.com/OAE/understanding-using_OAE%20von%20Kemp.pdf
Trnovec, T., Šovčíková, E., Pavlovčinová, G., Jakubíková, J., Jusko, T., Husťák, M., Jurečková, D., Palkovičová, L., Kočan, A., Drobná, B., Lancz, K., & Wimmerová, S. (2010). Serum PCB Concentrations and Cochlear Function in 12-Year-Old Children Environmental Science & Technology, 44 (8), 2884-2889 DOI: 10.1021/es901918h
Trnovec et al. also observed differences between ears (no, not that some kids heads were filled with Kapok and some weren't) with the left ear showing a stronger deficit than the right. This does lead one to wonder if people are left earred or right-earred and that the same effect might not be seen if they had recruited only right-handed or left-handed children. This is also more complex than it seems because you can be right handed and "goofy footed" i.e. left foot dominant. I am goofy footed, but its only apparent when I'm out surfing.
Here is a link for understanding the systems through which Trnovec are evaluating correlations of PCB exposure with hearing. http://www.est-med.com/OAE/understanding-using_OAE%20von%20Kemp.pdf
Trnovec, T., Šovčíková, E., Pavlovčinová, G., Jakubíková, J., Jusko, T., Husťák, M., Jurečková, D., Palkovičová, L., Kočan, A., Drobná, B., Lancz, K., & Wimmerová, S. (2010). Serum PCB Concentrations and Cochlear Function in 12-Year-Old Children Environmental Science & Technology, 44 (8), 2884-2889 DOI: 10.1021/es901918h
Thursday, December 30, 2010
Triclosan induces hypothyroidism and is transfered to infants during lactation.
Triclosan is used in many personal care products as an anti-bacterial agent. You can find it in soaps, toothpaste etc. It is also an endocrine disruptor that effects at least two different (albeit interrelated) systems. Triclosan has some estrogenic effects. Paul et al. (Dec 2010) have demonstrated that triclosan alters thyroid hormone levels early in lactation. Thyroid hormones are especially important during fetal and infant development because they play crucial roles in brain development. Early thyroid hormone deficiency alters neurological function in animals, and in human, reduces IQ and increases ADHD-like behavior. There are many environmental contaminants that interfere with thyroid hormones including PCBs, PBDEs, perchlorate, and nitrate. It is difficult to study the impact of exposures to these chemicals in humans because its hard to know how much people are exposed to over time, and people are probably never exposed to just one agent at a time. Its important to consider additive (or synergistic or antagonistic) effects and not consider them individually. For now, its probably best for pregnant and lactating women to limit their exposure to triclosan. Thank you, Paul et al., for your hard work, and for fitting yet another piece into the puzzle. Here is the U.S. FDA's position on Triclosan safety.
as of today.
Paul KB, Hedge JM, Devito MJ, & Crofton KM (2010). Developmental triclosan exposure decreases maternal and neonatal thyroxine in rats. Environmental toxicology and chemistry / SETAC, 29 (12), 2840-4 PMID: 20954233
as of today.
Paul KB, Hedge JM, Devito MJ, & Crofton KM (2010). Developmental triclosan exposure decreases maternal and neonatal thyroxine in rats. Environmental toxicology and chemistry / SETAC, 29 (12), 2840-4 PMID: 20954233
Friday, December 24, 2010
Fried food may cause diabetes in thin people too.
A Taiwanese research group published on the effects of high oxidized frying oil on insulin secretion (reduces insulin secretion)in 2007. In this study they (Chiang et al. 2010) attempt to determine the cause by experimenting with mice. They used three treatment groups:
Low Fat Diet
High Fat Diet
High Oxidized Frying Oil Diet.
The mice fed high oxidized frying oil exhibited reduced insulin secretion and high blood glucose levels. Very important here: their islets of langerhans (the tissue that produces insulin, as well as glucagon) showed evidence of oxidative damage. Glucagon and insulin work together to keep blood sugar stable. It seems likely that oxidative damage would occur throughout the body, so its probably best to avoid fried food even if diabetes or metabolic syndrome is not one of your concerns.
The High Fat diet mice did not show such changes. This implies that a diet high in fried food may put people at risk of diabetes or metabolic disorder by interfering with production of hormones regulating blood sugar, while a high fat diet of unoxidized oil might be just fine. Vitamin E is an important anti-oxidant and is protective against the effects of High Oxidized Frying Oil. Chiang et al. found that adding Vitamin E to the diet reduced the effects of the Oxidized Fat diet. Thanks to all for their hard work.
Ya-Fan Chiang, Huey-Mei Shaw, Mei-Fang Yang, Chih-Yang Huang, Cheng-Hsien Hsieh and Pei-Min Chao (2011). Dietary oxidised frying oil causes oxidative damage of pancreatic islets and impairment of insulin secretion, effects associated with vitamin E deficiency British Journal of Nutrition : 10.1017/S0007114510005039
Chao, P., Huang, H., Liao, C., Huang, S., & Huang, C. (2007). A high oxidised frying oil content diet is less adipogenic, but induces glucose intolerance in rodents British Journal of Nutrition, 98 (01) DOI: 10.1017/S000711450769000X
Low Fat Diet
High Fat Diet
High Oxidized Frying Oil Diet.
The mice fed high oxidized frying oil exhibited reduced insulin secretion and high blood glucose levels. Very important here: their islets of langerhans (the tissue that produces insulin, as well as glucagon) showed evidence of oxidative damage. Glucagon and insulin work together to keep blood sugar stable. It seems likely that oxidative damage would occur throughout the body, so its probably best to avoid fried food even if diabetes or metabolic syndrome is not one of your concerns.
The High Fat diet mice did not show such changes. This implies that a diet high in fried food may put people at risk of diabetes or metabolic disorder by interfering with production of hormones regulating blood sugar, while a high fat diet of unoxidized oil might be just fine. Vitamin E is an important anti-oxidant and is protective against the effects of High Oxidized Frying Oil. Chiang et al. found that adding Vitamin E to the diet reduced the effects of the Oxidized Fat diet. Thanks to all for their hard work.
Ya-Fan Chiang, Huey-Mei Shaw, Mei-Fang Yang, Chih-Yang Huang, Cheng-Hsien Hsieh and Pei-Min Chao (2011). Dietary oxidised frying oil causes oxidative damage of pancreatic islets and impairment of insulin secretion, effects associated with vitamin E deficiency British Journal of Nutrition : 10.1017/S0007114510005039
Chao, P., Huang, H., Liao, C., Huang, S., & Huang, C. (2007). A high oxidised frying oil content diet is less adipogenic, but induces glucose intolerance in rodents British Journal of Nutrition, 98 (01) DOI: 10.1017/S000711450769000X
Thursday, December 23, 2010
Autoimmune disease and inhalation of particulates
Airborne particulate matter appears to increase risk of diabetes, as discussed a few posts down and diabetics appear to have altered immune function according to a number of parameters. Diabetics have now been observed to have stronger indicators of immune response when air pollution levels (particulate matter in this case) are high. Schneider and Alexis (2010 . . . two first authors, congratulations all) observed increased blood levels of endogenous promotors of Activated Protein C Resistance. Diabetics who were also obese, or who did not express GSTm1, (not having this, by the way, increases risk of a wide array of cancers) or who already had elevated HbA1C (this is an indicator of longer-term blood glucose levels) had the strongest response to particulate matter. So, are diabetics more vulnerable to challenges to the immune system? Do these challenges contribute to development of diabetes? Or is there an interplay in each (diabetes and immune response)alters the pattern of the other. Lets hope they don't progressively spiral over time and continued exposure. The cohort was small with only 20 subjects, but it would be interesting to look at response to particulate matter by age, or time since diagnosis of type II diabetes.
Schneider A, Alexis NE, Diaz-Sanchez D, Neas LM, Harder S, Herbst MC, Cascio WE, Buse JB, Peters A, & Devlin RB (2010). Ambient PM2.5-Exposure Up-regulates the Expression of Co-Stimulatory Receptors on Circulating Monocytes in Diabetic Individuals. Environmental health perspectives PMID: 21169129
Schneider A, Alexis NE, Diaz-Sanchez D, Neas LM, Harder S, Herbst MC, Cascio WE, Buse JB, Peters A, & Devlin RB (2010). Ambient PM2.5-Exposure Up-regulates the Expression of Co-Stimulatory Receptors on Circulating Monocytes in Diabetic Individuals. Environmental health perspectives PMID: 21169129

Monday, December 20, 2010
Inflammation, autoimmune disease, diabetes and gum disease
The other day I wrote about environmental agents increasing risk of obesity, diabetes and insulin resistance and mentioned an article associating exposure to particulate matter with increased incidence of diabetes and wondered about it. If, as the authors suggest, exposure to particulates results in low-level chronic inflammation, then other causes of chronic inflammation (like gum disease) should also be associated with increased risk of diabetes, insulin resistance or similar. A little poking around, and yes, looks like a hit: Increased Prevalence of Cardiovascular and Autoimmune Diseases in Periodontitis Patients: A Cross-Sectional Study. Just out last month by Nesse et al. at the University of Groningen in The Netherlands. Very cool guys. Congrats on the publication.
Nesse W, Dijkstra PU, Abbas F, Spijkervet FK, Stijger A, Tromp JA, van Dijk JL, & Vissink A (2010). Increased prevalence of cardiovascular and autoimmune diseases in periodontitis patients: a cross-sectional study. Journal of periodontology, 81 (11), 1622-8 PMID: 20583916
Nesse W, Dijkstra PU, Abbas F, Spijkervet FK, Stijger A, Tromp JA, van Dijk JL, & Vissink A (2010). Increased prevalence of cardiovascular and autoimmune diseases in periodontitis patients: a cross-sectional study. Journal of periodontology, 81 (11), 1622-8 PMID: 20583916
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