However, the American Academy of Pediatric Dentistry say that more research is necessary before recommending xylitol to improve dental health in children. Manufacturers use a range of low-calorie artificial sweeteners and sugar substitutes to sweeten foods and beverages. Many of these substitutes are also available as table-top sweeteners, and some people use them in baking. Some substitutes are significantly sweeter than table sugar. However, the sweetness of xylitol is very similar to that of table sugar.
Sorbitol is a sugar alcohol with a similar molecular structure to xylitol. Sorbitol does not spike blood glucose levels, so it is a good sugar substitute for people who have diabetes.
Erythritol is another sugar alcohol. Similarly to xylitol, erythritol also inhibits the growth of S. A review found that high concentrations of erythritol are more effective at reducing oral plaque than both xylitol and sorbitol.
However, xylitol is more effective than erythritol at lower concentrations. A range of erythritol sweeteners is available to purchase online. Stevia is natural sweetener that manufacturers extract from the stevia plant. Stevia extract is available in granular and liquid forms. Purified leaf extract is — times sweeter than sugar. Stevia extract sweetening products are available to purchase online. Agave nectar is a syrup that manufacturers extract from the agave plant and use as a sugar substitute in some drinks and foods.
However, agave nectar mainly contains fructose, which bacteria in the mouth can break down into the acids that cause tooth decay.
Many agave nectar products are available to purchase online. Xylitol is a reduced-calorie sugar substitute similar in sweetness to table sugar. Xylitol also has a low GI, which makes it an attractive alternative to sugar for people wishing to lose weight and those with diabetes. Some research also suggests that xylitol has antibacterial properties that can help prevent tooth decay, gum disease, and ear infections.
However, further research into the potential health benefits of xylitol is needed. Erythritol is a popular artificial sweetener that is also a sugar alcohol. Manufacturers add a synthetic type of this chemical to diet foods and…. Ear infections are the most common reason parents take children to the doctors. MNT explains ear infections and how to treat them. To choose the best toothpaste, people need to consider a range of factors.
These include fluoride content and whether or not the American Dental…. Agave is a succulent plant which produces a naturally sweet nectar. People with diabetes need to find replacements for sugar or limit intake.
Is agave…. Stevia is a popular sugar substitute that is to times sweeter than table sugar yet has few calories. It is considered to have potential health….
What are the health benefits of xylitol? For the present purpose, glucose, galactose, and fructose are shown without specifying the configuration i. When a person consumes solutions containing excessive amounts of carbohydrates and polyols or salt , water can draw from the body into the gut lumen, causing osmotic diarrhea. This can naturally also result from a disease condition such as pancreatic disease.
Although the present review will focus only on cases with osmotic diarrhea that may occur in healthy subjects who consume excessive quantities of sugar alcohols, it is necessary to recall that acute osmotic effects may also result from consuming too great a quantity of processed grains and cereals [ 16 ] and certain fruits and vegetables [ 17 ] vide infra , Section 3. In healthy individuals, too-large quantities of common substances such as vitamin C, magnesium salts, lactose, and certain antibiotics may cause severe cases of osmotic diarrhea and bowel distension.
Owing to its simple physical cause, osmotic diarrhea normally stops completely when the use of the offending agent is discontinued. Experiments involving oral administration of sugar alcohols have normally been carried out using glucose or fructose as comparisons.
It has been found that, in most subjects, glucose has no laxative effect even in extraordinarily high dosages. Fructose represents an important point of comparison, since consumers' own judgments as to the origin of osmotic diarrhea following consumption of sugar alcohols are often confused by simultaneous consumption of fructose.
The role of fructose and d -glucitol in the etiology of IBS has been somewhat controversial when these substances are ingested together [ 18 ]. It nevertheless appears that the degree of symptom provocation is related to the amounts present in such a mixture but may not be related directly to the extent of colonic hydrogen production [ 18 ]. Sugar alcohols behave in the gut lumen in different ways, and their effects are not identical. Sugar alcohol molecules react in the gut lumen as physical and chemical entities based on their molecular mass, number of hydroxyl groups present in the molecule, the spatial orientation of those groups, and the overall symmetry of the molecule.
The number of OH groups present in these molecules is shown in Table 1 , which also reveals how the praxis of expressing concentrations differs significantly. These differences have also generated misunderstandings, since most clinical and nutritional reports customarily give the amount of sugar alcohols as percentages.
The true chemical concentrations can be significantly different, however. The case of erythritol and sucrose serves as an example. In physiological studies, it may be preferable to use chemical activities, that is, the chemical concentrations molarities , to make the cases chemically comparable. The intestinal absorption of xylitol is almost totally limited to the mechanism of permeation which applies to all strongly hydrophilic substances.
The driving force behind free diffusion of xylitol is the direction of the concentration gradient between the intestinal lumen and the outside compartment [ 1 , 3 , 4 , 8 — 14 , 19 ]. These papers have concluded, among other things, that in case facilitated diffusion of xylitol is involved, the transport system must exert very low affinity to xylitol.
In free diffusion, the uptake of the substance from the intestinal lumen takes place because of a simple physicochemical process through the hydrophobic pores in the membrane. In this process, molecular size is of particular significance. This parameter is to a certain extent indicated by the molecular weight of the substance. It is obvious that relatively extended molecules are in themselves ill-suited to the permeation process. The xylitol molecule is totally symmetrical and small compared with the d -glucitol molecule whose molar mass and dimensions are larger and which is also relatively asymmetrical in the latter molecule, the hydroxyl groups on C4 and C5 are in the d -configuration.
The molar mass and symmetry of d -mannitol also differ significantly from those of xylitol. Hence the consumption of d -glucitol and d -mannitol generates far more severe gastrointestinal disturbances than xylitol. A comparison between the molecular weights of xylitol In this comparison, the intestinal uptake of d -glucitol While glucose is virtually completely absorbed in the upper part of the small intestine, xylitol is normally only partly absorbed in the upper part and is present in considerable amounts in the lower region of the small intestine.
However, this depends on the quantity of xylitol consumed. Experience from the Finnish Turku Sugar Studies [ 4 , 20 ] also indicated that xylitol-associated diarrhea can be prevented by simultaneous administration of bulky food.
However, bulky food does not considerably increase the absorbability of xylitol, since the preventive effect results primarily from delayed emptying of the stomach. The presence of plant fibers may bind water, mitigating xylitol-associated diarrhea. As soon as the causative agent xylitol is removed, the tendency of osmotic diarrhea passes. Also, no irritation is generally observed in mucous membranes, except in extreme instances. Total absorption of xylitol and lessened osmotic diarrhea are more likely to occur when smaller quantities are consumed as part of a regular diet.
When xylitol is administered in an isolated form in beverages, the xylitol molecules are no longer sufficiently absorbed in the small intestine and will reach the colon. This concerns other pentitols and all hexitols as well. Therefore, consumption of polyol-containing beverages—apart from those based on erythritol—is not generally recommended.
In the colon, bacterial action converts d -glucitol to low-molecular decomposition products with much higher osmotic potential than in the case of xylitol. A form of adaptation to xylitol was first discovered in animal feeding studies and subsequently also in humans. Most notably this phenomenon was discovered in the two-year xylitol feeding study in Turku [ 4 , 20 ]. This adjustment has normally been linked to an enzyme induction; the activity levels of liver sorbitol dehydrogenase which catalyzes the initial oxidation of xylitol increase during habitual consumption of xylitol.
The largest single boluses of sugar alcohols that can elicit osmotic diarrhea in adult subjects differ based on experimental details. Typical results obtained in feeding studies are shown in Table 2. Such values must not be regarded as universally valid. The true effects depend on circumstances; evaluations conducted by different research teams may not be exactly congruent. Maximum bolus doses of some dietary sugar alcohols not causing catharsis.
Based on de Cock [ 15 ]. Based on the interest focused on diets that reduce intake of poorly absorbed small-molecular-size carbohydrates, a particular FODMAP concept was developed [ 16 , 17 , 21 — 25 ]. It is important to emphasize the role of polyols, such as xylitol, d -glucitol, and d -mannitol, in the FODMAP group of carbohydrates. Although sugar alcohols can be used to alleviate chronic constipation, it is thus obvious that sugar alcohols—with the exception of erythritol—should generally be avoided as part of low FODMAPs diet.
Older literature is cited here on purpose in order to emphasize the existence of gradually growing clinical interest in this area of research. One of the earliest scientific reports on the very slow absorption rate of d -glucitol was published by Dahlqvist and Telenius [ 26 ].
Intractable diarrhea associated with the use of d -glucitol has later been frequently reported in the clinical literature.
This has most often resulted from the use of d -glucitol as a sweetener and bulking agent in dietetic candies and chewing gum, although use of d -glucitol as a vehicle for suspending active drugs for oral preparations can also cause intractable diarrhea [ 27 ]. The situation was partly a result of the limited information available in pediatric textbooks concerning diarrhea caused by poorly absorbed osmotically active substances. Pediatric gastroenterology texts contained only passing references to this form of diarrhea, caused by dietetic, d -glucitol-containing candies or chewing gum [ 31 , 32 ].
A typical case report normally follows a series of events similar to the following example: A 3-year-old boy consumes six full packs of a d -glucitol chewing gum brand. As late as , physicians alerted public health experts to the diarrheal potential of d -glucitol [ 34 ], as the quantities of d -glucitol used in the candy and food industry increased significantly. The popular use of d -glucitol in cough mixtures, cough drops, and various pharmaceutical syrups also began to receive attention; all of them have been reported as potential causes of diarrhea especially in infants.
Such products were, however, beneficial from a dental standpoint, provided that d -glucitol replaced all fermentable carbohydrates previously used in such products. This was clearly a positive property of d -glucitol-containing items. It is well known that d -glucitol and d -mannitol are present in a wide variety fruits and other plant material [ 16 , 17 ]. The concentration of d -glucitol in dried fruit, such as prunes, may reach levels that can contribute to diarrhea.
Anecdotal evidence suggests that, historically, pediatricians advised mothers to give prunes to children with constipation. Modern scientific research concerning the FODMAPs concept has, however, more quantitatively underlined the role of d -glucitol and d -mannitol in osmotic diarrhea and their occurrence in natural products [ 16 , 17 ] vide supra.
As stated above, IBS was also reported to result from the ingestion of mixtures of fructose and d -glucitol [ 18 ]. Yao et al.
Both alditols induced gastrointestinal symptoms in patients with IBS independently of their absorptive pathway, indicating that dietary restriction of the alditols may be efficacious. Xiao et al. Similar comments have been made elsewhere [ 35 , 36 ], with evidence that particularly fructose conditions the gut microflora. Recent IBS papers included those of Shepherd et al. Some researchers also interpreted other d -glucitol effects as positive: d -glucitol therapy reportedly improved psychomotor performance in cirrhotic patients [ 29 ].
Patients with hepatic encephalopathy improved in all five mental function tests, whereas similar patients not receiving d -glucitol showed no improvement. A comparison between d -glucitol and lactulose showed that both were extensively fermented by the colonic flora [ 42 ].
It was suggested that the much cheaper d -glucitol could be used in the treatment of postsystemic encephalopathy. The medical literature has, however, simultaneously been replete with case reports and clinical studies relating detrimental d -glucitol effects, that is, intolerance to this sugar alcohol, as evidenced by the literature references shown above.
A debate on the possibility of glucose-stimulated influx of d -glucitol across the human jejunal mucosa has continued since the late s [ 43 ]. Owing to the hydrolytic cleavage of maltitol by intestinal enzymes, free glucose and free d -glucitol are formed. The liberated glucose molecules are absorbed virtually completely, whereas the liberated d -glucitol is incompletely absorbed, contributes to osmotic diarrhea, and is eventually subject to microbial fermentation in the gut.
Zunft et al. An increased breath H 2 response indicated primarily colonic maltitol fermentation [ 45 ]. Another study reported that occasional or regular consumption of maltitol was not associated with severe digestive symptoms [ 46 ]. The symptoms could be suppressed by simultaneous ingestion of partially hydrolyzed guar gum which consists of the ground endosperm of guar a legume seeds.
The gum, which swells and disperses in water, contains a mannose- and galactose-based polysaccharide, guaran. It may be of interest that maltitol has been shown to protect against dimethylhydrazine-induced tumours in rat caecum and proximal colon. This may result from butyric acid formation [ 47 ].
Another possible benefit is the maltitol-associated promotion of calcium absorption and advantageous bone effects in rat models [ 48 , 49 ], a reaction that has also been observed with xylitol [ 50 ]. The intact portion of isomalt and the unabsorbed d -glucitol and d -mannitol molecules eventually reach the lower parts of the gut where they serve as substrates for bacterial formation of volatile fatty acids. Consequently, isomalt can pass through the bowel partly undigested; part of it is hydrolyzed in the small intestine.
Habitual consumption of isomalt may lead to partial adaptation, which suggests decreased occurrence of gastrointestinal changes. Isomalt could be used as an alternative to lactulose for colonic delivery system utilizing the principles of a unique colon-specific delivery technique called CODES [ 51 ]. Since d -glucitol has been associated with greater colonic fermentation compared with isomalt [ 52 ], its formation from the latter should be considered.
After reaching the large intestine, the lactitol molecules can pull water into the gut lumen by simple osmosis. True loading tests with lactitol are limited. Compare also with Natah et al. In conclusion concerning disaccharide sugar alcohols, excessive consumption of maltitol and isomalt can cause significant osmotic diarrhea and flatulence. True gastrointestinal loading tests on lactitol should be repeated.
The amount of disaccharide polyols present in chewing gum is too low to cause any gastrointestinal effects in most subjects. The GOSs are not sugar alcohols but may occasion similar gastrointestinal disturbances as the latter.
Historically, the GOS group of carbohydrates deserve attention in this context because of the presence of GOS in some polyol-containing manufactured foods. Indeed, field experience suggests that consumers frequently misjudge the causative food agent when simultaneously consuming raffinose-based food of a leguminous nature and sugar alcohol-containing confectionaries or medicines. Therefore, the role of GOS will be concisely discussed here. Legumes, rich in GOSs, normally contain only insignificant quantities of sugar alcohols.
Oligosaccharides began to receive more attention as a result of the growing interest in bringing new sources of protein into the food system, including soybeans, which contain these sugars. Nor are oligosaccharides resorbed by the intestinal wall, owing to their high molecular weight. Consequently, they come in contact with bacteria that inhabit the lower parts of the intestine. The bacteria are able to utilize the raffinose-family oligosaccharides with subsequent formation of flatus [ 55 ].
These oligosaccharides may also promote the growth of bifidobacteria in the human intestine and cause diarrhea when consumed in excess of a particular quantity [ 56 ]. The molecular weight of oligosaccharides has an influence on flatus formation.
These compounds include stachyose molar mass A holoside is a glycoside that yields only glycoses on hydrolysis. Both have marked effects as flatus formers. Raffinose or melitose; The objective of emphasizing the role of ordinary leguminous plants as a source of flatus and diarrhea is to underline the role of regular human food as another common source of gastrointestinal discomfort. Flatulence is an old problem; the first scientific reports dealing with it were published early in the last century.
Even a slight increase in pressure in rectal gas may lead to symptoms of discomfort. Researchers discovered about fifty years ago that some GOSs play a part in flatus formation. Flatus is often accompanied by a lowering of the pH. The lowered pH may in turn affect the metabolism of other substances [ 57 , 58 ]. Microbial fermentations of GOS in the large intestine are responsible for flatus components such as hydrogen, methane, and carbon dioxide.
Oxygen and nitrogen may also be present and originate from swallowed air. Significant, positive correlations were discovered between hydrogen production and the following chemical components that are present in various pea varieties: stachyose and raffinose and various glucans and pentosans. Glucose and galactose which are common dietary carbohydrates can be concentrated against a tenfold gradient by an active transport mechanism that assures their early absorption in the intestinal tract [ 6 , 13 , 19 , 20 , 60 , 61 ].
The question is of a facilitated transport mechanism. In the case of xylitol and d -glucitol, however, there is no evidence of such transport mechanisms [ 3 , 60 — 66 ].
As mentioned above, their absorption takes place based on free diffusion, or, if an active transport system exists, it has only a low affinity. The driving force behind free diffusion is the concentration difference for the substance in question [ 65 — 67 ]. Another factor limiting diffusion is the pore size [ 68 ]. The diameter of hydrophilic pores may range considerably from less than one nanometer to between 0.
Although the molecular weights of xylitol The symmetrical configuration of the xylitol molecule may facilitate a single-file diffusion of the molecule through tunnels. The greatest portion of absorbed xylitol is metabolized in the liver, although kidneys and other tissues are also sites of xylitol metabolism [ 19 , 54 ].
Red blood cells metabolize xylitol readily. Most xylitol is metabolized by a pathway involving normal, physiologic enzyme-catalyzed steps of the pentose phosphate pathway. This pathway is a portion of the glucuronate-xylulose cycle, also called Touster's cycle that was introduced already in the s and s [ 60 , 62 — 66 ]. It has been difficult to visualize in practical terms the link between this cycle and the better-known glycolysis.
The identity of the enzymes involved in this cycle and the overall metabolism of xylitol in human tissues was established by the mids, when the United States FDA released its expert opinion on the safety of xylitol and lactose. Relationship between the metabolism of xylitol and glycolysis in humans. The scheme describes the metabolism of dietary xylitol in broad outline only. The body receives energy from glycolysis the thick horizontal arrow.
The first intermediate of glycolysis is glucose 6-phosphate which forms an important link between glycolysis and another metabolic pathway, called the pentose phosphate shunt, or pentose phosphate cycle curved arrow. The thinner black arrow represents the glucuronate-xylulose cycle of Touster. The differences in the thickness of the arrows reflect the relative portion of these three pathways in the overall metabolism. Although the significance of the Touster cycle is minor from the energetic point of view, it is nevertheless absolutely necessary for body functions.
Pyruvic acid which may be regarded as the end product of glycolysis can be further metabolized in two ways: reduction to lactic acid under conditions of limited oxygen supply, or becoming a part of coenzyme A when the oxygen supply is sufficient. The scheme shows how xylitol can contribute to the overall energy metabolism of the body. Few research papers have reported on gastrointestinal changes during xylitol consumption. This partly results from the nonexistence of such changes in clinical trials aimed at investigating oral biologic and dental effects of xylitol.
In most stomatologic studies, xylitol consumption levels have been relatively small, and, consequently, the researchers did not need to focus on possible side effects of xylitol consumption. The scantiness of such reports is unfortunate, since the next generation of consumers, health-care authorities, and medical and dental practitioners has retroactively started to ask for hard data on the relationship between the consumption of xylitol and bowel movements, flatulence, meteorism, and other bowel reactions.
Observations on the occurrence of diarrhea in studies involving consumption of xylitol and other dietary alditols will be reviewed below, as reported by the authors of those studies. The individual studies are summarized instead of showing study details in the form of tables.
This results from the publication of several early studies in difficult-to-locate journals, which have not provided abstracts of papers. Since these studies represent real-life situations, their review enables present readers to obtain direct information on the studies involved, with practical instructions regarding dosage levels of alditols for patient counselling purposes.
By the mids, various medical and dental benefits of xylitol were already known. Considerable experience had become available since the s from the former Soviet Union, where the metabolism and uses of xylitol for nutritive and medical purposes had become a favored research topic.
The Soviet researchers were not aware of the dental effects of xylitol until the publication of the Finnish Turku Sugar Studies in [ 20 ]. This study prompted Galiullin [ 60 ] to undertake a two-year xylitol trial in the state of Kazan. His results were in line with those of the Turku study vide infra. Some Russian-language medical articles have been difficult to access, but a valuable contribution to this xylitol literature was made by Dr.
Nesterin from the Moscow Nutrition Institute. He wrote a comprehensive historic review of the Soviet investigations into the general medical effects of xylitol, including its toxicity, influence on bodily functions in diabetes mellitus , disorders of the hepatobiliary system, and other medical conditions. This Russian-language article was translated into English and appeared in in a German scientific journal [ 13 ].
Although the article focused on diabetes and disturbances of the liver and gallbladder system, observations on gastrointestinal effects of xylitol were also made. Nesterin also described a large number of animal experiments. The direct quotes below are examples from the translation. Nesterin's review showed that the Soviet medical authorities recommended xylitol in the treatment of various medical conditions.
In the mids, the present author received a personal report from Dr. No side effects were observed. Her patients also included diabetic subjects who had frequent pain in the right hypochondrium and suffered from constipation.
It is also possible that the patients' meals contained water-absorbent dietary fibers which may have alleviated gastrointestinal responses. In other experiments a general improvement in the diabetic state of a large number of diabetic subjects was observed.
An expected observation was the relief of constipation some subjects suffered. Domareva in Vopr. Pitanija , No. Marshak and I. Savoshtshenko in Med. Gazeta , No. Coinciding with the publication of the above Soviet experiences in the German medical journal, several research groups in Germany got engrossed in detailed gastrointestinal studies with xylitol.
Research teams in other countries followed suit. The following twenty reports provide quantitative information on osmotic diarrhea associated with the consumption of xylitol by human subjects. Dubach et al. Intolerance was not observed. At this level, aversion to sweets was noted. Body weight, fasting blood sugar values, and stool consistency remained uninfluenced. Twenty-one subjects out of 26 preferred xylitol over d -glucitol; meteorism and flatus were more common with d -glucitol at the same dose.
Asano et al. This study was described in detail by Brin and Miller in [ 69 ]. A long-term feeding trial on xylitol was carried out in — in Turku, Finland [ 4 , 20 ]. Three groups of volunteers, totalling , lived for two years on strict diets so that comparisons could be made with regard to the sweeteners tested: sucrose S , fructose F , and xylitol X.
These diets were given to the subjects free of charge from the institute carrying out the research. A total of about twelve food manufacturing enterprises participated in providing a wide variety of food items for the subjects [ 4 , 20 ]. Consequently, since this study remains the only long-term true feeding trial with any sugar alcohol conducted in humans and since the above publication a supplement to Acta Odontologica Scandinavica has not been readily available, this research is summarized below.
The sizes of the test groups were S, 35; F, 38; X, The calculated consumption value for sucrose was most likely somewhat higher, since subjects were known to consume food obtained from other sources. The subjects were continuously monitored by medical research teams. The study showed that the consumption of xylitol and fructose was associated with osmotic diarrhea, flatulence, and gastric distress. The ability of xylitol to produce gastrointestinal disturbances was found to depend on individual physiological responses in each volunteer.
In many cases, subjects reported no symptoms even though high amounts of xylitol were consumed. All pregnancies and deliveries in the xylitol group were normal. The illustration shows the number of subjects who reported loose stools during the first days of the trial.
As expected, several subjects experienced loose stools during the first weeks. After the first days, the frequency of symptoms continued almost unchanged for the rest of the study.
Consequently, during the last days of the feeding trial, the occurrence of diarrhea in the xylitol group was nearly of the same frequency as in the sucrose and fructose groups; that is, the reports about diarrhea decreased to about one-quarter compared to the first weeks.
The total number of intakes of xylitol-containing food items was , over the course of the two-year trial, or about reported intakes of xylitol food per subject and per month.
A total of 35 subjects in the xylitol group were considered as having consumed exceptionally high quantities of xylitol. The results are here shown for the first day period. The ordinate gives the number of subjects complaining even about slight diarrhea or increased defecation frequency on each test day. The initial peaks of consumption were found to result from the interest of the subjects to get acquainted with the new dietary regimen. Modified from [ 4 ]. Out of the initial number of subjects 57 who started the xylitol regimen, five discontinued the program as a result of study fatigue 2 subjects , poor compliance one subject , employment reasons one subject , and reported persistent diarrhea one subject.
The final medical reports including gastrointestinal information were thus available from 52 xylitol-consuming subjects. The more xylitol you take in, the more likely you are to experience this unwanted effect. Interestingly, other sugar alcohols like erythritol don't cause this negative reaction.
Additionally, erythritol outperformed xylitol on oral-health measures — better decreasing, for example, the buildup of dental plaque, so you get the benefits without the side effects. The authors of a January report from the International Food Information Council suggested that you can take between 20 and 70 milligrams of xylitol each day without experiencing side effects.
Yet your tolerance level might be different, so you will have to stay vigilant. For perspective, one piece of sugar-free gum and candy contains about milligrams of xylitol, according to August University, Dental School of Georgia. Your body doesn't fully process xylitol, and that might cause you to experience bloating and gas.
These symptoms can also lead to problems for those suffering from irritable bowel syndrome. Chemists classify xylitol as polyol, so people on the FODMAP diet should carefully watch their xylitol intake or avoid it altogether.
It's important to keep xylitol away from dogs, according to a July warning from the U. Food and Drug Administration , because it can be deadly. If you suspect xylitol poisoning in your dog, immediately contact your veterinarian. Nutrition Cooking and Baking Sweeteners. Jill Corleone is a registered dietitian with more than 20 years of experience.
Bryan Myers. Bryan Myers writes wellness articles as a social activist working from a scientific perspective. Extensively trained in nutrition and fitness, he has presented his theories and research in medical journals. Myers has also written hundreds of health articles as a science journalist. He has degrees in experimental psychology from the University of Toledo and in behavioral neuroscience from Bowling Green State University.
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