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From Swedish Fish to fun-size Twix, I tested Halloween candy as fuel for long runs. Here's how they compare to traditional sports nutrition--and ones that won't haunt your training. New [...]

You're on course cross-country in your horse's first Preliminary-level event. You trained for months to bring him here, building his stamina-or so you thought. But now, with a half dozen [...]

Nutritionally speaking, the post-training meal is the most forgiving time of day. If you're harboring a wicked urge to cheat and you just can't rein it in, at least wait [...]

Background: Cross-sectional studies indicate that diets that provide a higher dietary glycemic index (dGI) are associated with a greater risk of age-related macular degeneration (AMD). No prospective studies have addressed this issue. Objective: The objective was to prospectively evaluate the effect of baseline dGI on the progression of AMD. Design: dGI was calculated as the weighted average of GIs from foods and was evaluated as being above or below the sex median (women: 77.9; men: 79.3) for 3977 participants aged 55-80 y (58% women) in the Age-Related Eye Disease Study. The 7232 eligible eyes without advanced AMD were classified into 1 of 3 AMD categories: group 1 (nonextensive small drusen), group 2 (intermediate drusen, extensive small drusen, or pigmentary abnormalities), or group 3 (large drusen or extensive intermediate drusen). With the use of multifailure Cox proportional-hazards regression, we modeled the time to the maximal progression to evaluate the relation between dG1 and the risk of AMD. Results: Overall, the multivariate-adjusted risk of progression over 8 y of follow-up ([bar.x]: 5.4 y) was significantly higher (risk ratio: 1.10; 95% CI: 1.00, 1.20: P = 0.047) in the high-dGI group than in the low-dGI group. The risk of progression for groups 1, 2, and 3 eyes was 5%, 8%, and 17% greater, respectively (P for trend < 0.001). The latter gives an estimate that 7.8% of new advanced AMD cases would be prevented in 5 y if people consumed the low-dGl diet. Conclusion: Persons at risk of AMD progression, especially those at high risk of advanced AMD, may benefit from consuming a smaller amount of refined carbohydrates. KEY WORDS Retina, nutrition, carbohydrate, diabetes, sugar, glycation, inflammation, aging, stress, epidemiology

Background: Dietary carbohydrate intake has been shown to increase the plasma concentration of tryptophan, a precursor of serotonin and sleep-inducing agent. Objective: To investigate the role of carbohydrate in sleep induction, we explored the effect of glycemic index (GI) and meal time on sleep in healthy volunteers. Design: We compared the effect of high- and low-GI carbohydrate-based meals ingested 4 h before bedtime on sleep quality. We also evaluated the effect of the timing of high-GI meals (4 h compared with 1 h) on sleep quality. Twelve healthy men (aged 18-35 y) were administered standard, isocaloric (3212 kJ; 8% of energy as protein, 1.6% of energy as fat, and 90.4% of energy as carbohydrate) meals of either Mahatma (low GI = 50) or Jasmine (high GI = 109) rice 4 h before their usual bedtime. On another occasion, the high-GI meal was given 1 h before bedtime. The participants underwent a familiarization night followed by 3 test nights in random order 1 wk apart. Results: A significant (P = 0.009) reduction in the mean ([+ or -] SD) sleep onset latency (SOL) was observed with a high-GI (9.0 [+ or -] 6.2 rain) compared with a low-GI (17.5 [+ or -] 6.2 min) meal consumed 4 h before bedtime. The high-GI meal given 4 h before bedtime showed a significantly shortened SOL compared with the same meal given 1 h before bedtime (9.0 [+ or -] 6.2 min compared with 14.6 [+ or -] 9.9 min; P = 0.01). No effects on other sleep variables were observed. Conclusions: We showed that a carbohydrate-based high-GI meal resulted in a significant shortening of SOL in healthy sleepers compared with a low-GI meal and was most effective when consumed 4 h before bedtime. The relevance of these findings to persons with sleep disturbance should be determined in future trials. KEY WORDS Carbohydrates, glycemic index, sleep quality, sleep timing

Background: Carbohydrate modification based on rye bread and pasta enhances early insulin secretion in subjects with the metabolic syndrome. Objective: Because the actions of insulin and cholesterol metabolism are interrelated, the question is raised of whether it is possible to alter cholesterol metabolism by means of dietary carbohydrate modification. Design: We investigated the 12-wk effects of dietary carbohydrate modification on cholesterol synthesis and absorption by measuring the ratios of surrogate markers of precursor (cholestenol, desmosterol, and lathosterol) and absorption (cholestanol and plant sterols) sterols to cholesterol and their association to glucose metabolism in 74 subjects with the metabolic syndrome. The subjects were randomly assigned to diets with rye bread and pasta (RPa) or oat, wheat bread, and potato (OWPo) as the main carbohydrate source (34% and 37% of energy intake, respectively). Results: During the study, serum cholesterol concentrations remained unchanged. Cholesterol synthesis was lower (6-10% for cholestenol and lathosterol; P < 0.05) and absorption higher (9%; P < 0.05 for sitosterol) with the OWPo diet than at baseline. With the RPa diet, cholesterol absorption was lower and synthesis higher than with the OWPo diet. The increment in the glucose area under the curve with the RPa diet was positively related to baseline cholesterol synthesis (eg, lathosterol; r = 0.480, P < 0.05) and negatively to absorption (for cholestanol; r = -0.520, P < 0.05). In the combined group, the changes in the cholestanol ratio and the insulinogenic index were interrelated (r = -0.464, P < 0.001). Conclusions: Carbohydrate modifications had dissimilar effects on cholesterol metabolism. Consumption of RPa, as compared with OWPo, may be clinically more favorable because it seems to inhibit the absorption of cholesterol, a factor crucial in the development of arterial atherosclerosis. KEY WORDS Rye, oat, wheat, metabolic syndrome, glucose metabolism, cholesterol metabolism, sitosterol, campesterol, lathosterol, randomized controlled trial

Background: A diet with a high glycemic index (GI) and glycemic load (GL) may promote overconsumption of energy and increase the risk of weight gain. Objective: The objective of the study was to investigate the relation between GI and GL of habitual diets and subsequent 6-y changes in body weight, body fat distribution, and body composition in a random group of adult Danes. Design: A prospective cohort study was conducted in a subsample of men and women from the Danish arm of the Monitoring Trends and Determinants in Cardiovascular Disease study. The subsample comprised 185 men and 191 women born in 1922, 1932, 1942, or 1952. A baseline health examination and a dietary history interview were carded out in 1987 and 1988; a follow-up health examination was performed in 1993 and 1994. Results: Positive associations between GI and changes in body weight ([DELTA]BW), percentage body fat ([DELTA]%BF), and waist circumference ([DELTA]WC) were observed in women after adjustment for covariates. Significant GI x sex x physical activity interactions for [DELTA]BW, [DELTA]%BF, and [DELTA]WC were observed, and the associations in the sedentary women were particularly positive. No significant associations with GI were observed in men, and no significant associations with GL were observed in either sex. Conclusions: High-GI diets may lead to increases in BW, body fat mass, and WC in women, especially in sedentary women, which suggests that physical activity may protect against diet-induced weight gain. No associations with GI were observed in men, which suggests sex differences in the association between GI and obesity development. KEY WORDS Diet, carbohydrate, obesity, adults, prospective cohort study, sex differences, glycemic index, glycemic load

Background: Determination of the metabolizable (ME) and net metabolizable (NME) energy of total carbohydrate requires estimation of its available (AC) and fermentable (FC) carbohydrate content. Modeling of indirect calorimetric observations (respiratory gas exchange) and breath hydrogen would appear to make it possible to estimate noninvasively these nutritional quantities and the approximate time-course of availability. Objective: We assessed the time-course of metabolism and energy availability from resistant maltodextrin (RMD) by modeling of respiratory gases after a single oral dose. Design: Seventeen healthy adults (13 M, 4 F; aged 25-46 y) were randomly assigned to treatments (water, maltodextrin, or RMD) in a multiple-crossover, single-blinded trial with [greater than or equal to]7 d washout. We monitored 8-h nitrogen-corrected oxygen and carbon dioxide exchanges and breath hydrogen All treatment groups took low-carbohydrate meals at 3 and 6 h. Results: Indirect calorimetry alone provided only qualitative information about the nutritional values of carbohydrate. In contrast, modeling of gaseous exchanges along with the use of central assumptions showed that 17 [+ or -]2% of RMD was AC and 40 [+ or -]4% was FC. As compared with 17 kJ gross energy/g RMD, mean ([+ or -]SE) energy values were 7.3 [+ or -] 0.6 kJ ME/g and 6.3 [+ or -]0.5 kJ NME/g. The fiber fraction of RMD provided 5.2 [+ or -] 0.7 kJ ME/g and 4.1 [+ or -] 0.6 kJ NME/g. Conclusions: Modeling with the use of this noninvasive and widely available respiratory gas--monitoring technique yields nutritional values for carbohydrate that are supported by enzymatic, microbial, and animal studies and human fecal collection studies. Improvement in this approach is likely and testable across laboratories. KEY WORDS Indirect calorimetry, available carbohydrate, fermentable carbohydrate, energy value, modeling, humans

Background: The metabolic syndrome markedly increases the risk of type 2 diabetes and cardiovascular disease, but the influence of dietary modification on insulin and glucose metabolism independent of weight loss is still poorly understood. Objective: Our aim was to test whether carbohydrate dietary modifications improve insulin sensitivity and secretion and glucose tolerance in overweight or obese persons with the metabolic syndrome, even in the absence of weight loss. Design: We assessed the effect of carbohydrate modification on insulin and glucose metabolism in 72 overweight or obese men and women with the metabolic syndrome, as determined according to the National Cholesterol Education Program criteria. The subjects were randomly assigned to 12-wk diets in which either rye bread and pasta or oat and wheat bread and potato were the main carbohydrate sources (34% and 37% of energy intake, respectively). Results: Body weight did not significantly change in either group during the trial. No significant difference was observed in the changes in fasting glucose and insulin concentrations or in glucose and insulin areas under the curve between the groups during a 2-h oral-glucose-tolerance test. The insulinogenic index (an index of early insulin secretion) increased more in the rye bread and pasta group than in the oat and wheat bread and potato group (33.2% compared with 5.5%; P = 0.026). In the combined groups, an enhanced insulinogenic index was associated with improved glucose tolerance, whereas weight gain worsened glucose tolerance. Moreover, even modest weight gains abolished the relative improvement in the insulinogenic index in the rye bread and pasta group compared with the oat and wheat bread and potato group (P for the interaction between weight change and group = 0.019). Conclusions: Rye bread and pasta-based carbohydrate modification enhances early insulin secretion in persons with the metabolic syndrome, which may lower the risk of deteriorating glucose tolerance and development of type 2 diabetes. KEY WORDS: Rye. oat, wheat, insulin secretion, glucose tolerance, metabolic syndrome, randomized controlled trial

Background: Animal studies suggest a role for dietary carbohydrate in cataractogenesis. However, few published human studies have evaluated associations between carbohydrate nutrition and lens opacification. Objective: Our objective was to test the hypothesis that long-term carbohydrate intake and dietary glycemic index are associated with the odds of early cortical and nuclear opacities. Design: Subjects were 417 Boston-area members of the Nurses' Health Study cohort aged 53-73 y. Dietary information was based on an average from 5 semiquantitative food-frequency questionnaires collected over a 14-y period. Opacities were assessed by using the Lens Opacity Classification System III (LOCS III). We used eyes (n = 711) as the unit of analysis and generated odds ratios by using a generalized estimating approach to logistic regression to account for the lack of independence between the 2 eyes of each subject. Results: After multivariate adjustment, the odds of cortical opacities (LOCS III [greater than or equal to] 1.0) among women in the highest tertile of carbohydrate intake ([greater than or equal to] 200 g/d) was 2.46 times (95% CI: 1.30, 4.64; P for trend = 0.005) that among women in the lowest tertile ( Conclusions: These data suggest that carbohydrate quantity, but not carbohydrate quality, is associated with early cortical opacities, and that neither the quantity nor the quality of dietary carbohydrate affects the risk of nuclear opacities in middle-aged women. KEY WORDS Cataract, lens, nutrition, carbohydrate, glycemic index, glycation, aging, stress, epidemiology, humans, risk factor

Background: The optimal nutritional approach for the prevention of cardiovascular disease among obese persons remains a topic of intense controversy. Available approaches range from conventional low-fat to very-low-carbohydrate diets. Objective: The aim of this pilot study was to evaluate the efficacy of an ad libitum low-glycemic load diet, without strict limitation on carbohydrate intake, as an alternative to a conventional low-fat diet. Design: A randomized controlled trial compared 2 dietary treatments in obese young adults (n = 23) over 12 too. The experimental treatment emphasized ad libitum consumption of low-glycemic-index foods, with 45-50% of energy from carbohydrates and 30 35% from fat. The conventional treatment was restricted in energy (250-500 kcal/d deficit) and fat ( Results: Body weight decreased significantly over a 6-too intensive intervention in both the experimental and conventional diet groups (-8.4% and -7.8%, respectively) and remained below baseline at 12 mo (-7.8% and -6.1%, respectively). The experimental diet group showed a significantly greater mean decline in plasma triacylglycerols than did the conventional diet group (-37.2% and -19.1%, respectively: P = 0.005). Mean plasminogen activator inhibitor 1 concentrations decreased (-39.0%) in the experimental diet group but increased (33. 1%) in the conventional diet group (P = 0.004). Changes in cholesterol concentrations, blood pressure, and insulin sensitivity did not differ significantly between the groups. Conclusion: An ad libitum low-glycemic load diet may be more efficacious than a conventional, energy-restricted, low-fat diet in reducing cardiovascular disease risk. 976-82. KEY WORDS Obesity, glycemic index, glycemic load, dietary composition, weight-reducing diet, cholesterol, triacylglycerol, plasminogen activator inhibitor 1, PAI-1, young adults

Background: Nondigestible carbohydrates (NDCHs) are fermented in the colon, where they can selectively promote the growth of bifidobacteria. Objective: Our aim was to determine the bifidogenic potential of different NDCHs used in human diets. Design: Two hundred healthy volunteers participated in this double-blind study. During phase 1 (screening), 64 volunteers were randomly assigned to 8 groups of 8 subjects each; for 7 d, they ingested 10 g/d of 1 of the 7 NDCHs tested or of the placebo. During phase 2 (dose-response study), 136 volunteers were randomly assigned to 4 groups of 32 subjects who received 2.5, 5.0, 7.5, or 10 g/d, respectively (8 subjects/dose), of one of the NDCHs that were proven to be bifidogenic during phase 1 and a fifth group of 8 subjects (control subjects) who received the placebo. Stools were recovered before and after NDCH consumption. Results: In phase 1, 4 NDCHs were found to be bifidogenic: short-chain fructooligosaccharides (P = 0.008), soybean oligosaccharides (P = 0.006), galactooligosaccharides (P < 0.0001), and type III resistant starch (P = 0.02); lactulose, long-chain inulin, and isomaltooligosaccharides were not bifidogenic. In phase 2, the effects of 7-d treatment on bifidobacteria concentrations were found to differ significantly among the 4 NDCHs (P = 0.009 for time x treatment interaction). However, no significant differences were found among doses, and there was no significant dose x time interaction. A low baseline bifidobacteria count was significantly associated with the bifidogenic response to treatment (P < 0.001). Conclusion: This study showed the different bifidogenic properties among the substrates and underlined the importance of taking into account the baseline bifidobacteria counts when evaluating the effect of the treatment. KEY WORDS Bifidobacterium, human fecal microflora, gut flora, nondigestible carbohydrate, oligosaccharides, prebiotics, randomized controlled trial

Background: The influence of diet on atherosclerotic progression is not well established, particularly in postmenopausal women, in whom risk factors for progression may differ from those for men. Objective: The objective was to investigate associations between dietary macronutrients and progression of coronary atherosclerosis among postmenopausal women. Design: Quantitative coronary angiography was performed at baseline and after a mean follow-up of 3.1 y in 2243 coronary segments in 235 postmenopausal women with established coronary heart disease. Usual dietary intake was assessed at baseline. Results: The mean ([+ or -] SD) total fat intake was 25 [+ or -] 6% of energy. In multivariate analyses, a higher saturated fat intake was associated with a smaller decline in mean minimal coronary diameter (P = 0.001) and less progression of coronary stenosis (P = 0.002) during follow-up. Compared with a 0.22-mm decline in the lowest quartile of intake, there was a 0.l0-mm decline in the second quartile (P = 0.002), a 0.07-mm decline in the third quartile (P = 0.002), and no decline in the fourth quartile (P < 0.00l); P for trend = 0.001. This inverse association was more pronounced among women with lower monounsaturated fat (P for interaction = 0.04) and higher carbohydrate (P for interaction = 0.004) intakes and possibly lower total fat intake (P for interaction = 0.09). Carbohydrate intake was positively associated with atherosclerotic progression (P = 0.001), particularly when the glycemic index was high. Polyunsaturated fat intake was positively associated with progression when replacing other fats (P = 0.04) but not when replacing carbohydrate or protein. Monounsaturated and total fat intakes were not associated with progression. Conclusions: In postmenopausal women with relatively low total fat intake, a greater saturated fat intake is associated with less progression of coronary atherosclerosis, whereas carbohydrate intake is associated with a greater progression. Am J Clin Nutr 2004:80: 1175-84. KEY WORDS Diet, saturated fat, carbohydrate, coronary atherosclerosis, women

Step 1: Know Your Carbs Carbohydrates are basically sugar and starch. There are two kinds: simple and complex. Glucose, a simple carb, is in your blood. Foods containing simple carbohydrates […]

FAT CITY, U.S.A. Stroll through a supermarket, and you're bombarded with low-carbohydrate labels. Open up a menu, and you're faced with Atkins-friendly treats. Flip through a magazine, and you're blasted [...]

Carbohydrates are at the center of a major food controversy, as followers of high-protein diets completely shun carbs while the American government and many health authorities insist that they are an important part of a balanced diet. A special report on the carbohydrates vs. proteins debate investigates this trend, and offers suggestions for the right carb choices for a healthy diet.

It's painful for some of us to even think about it. All those years of shunning cholesterol-laden eggs and choking down fat-free muffins appear to have been for naught. If [...]

PERHAPS YOU'VE seen at least one of those 'countdown' television shows: 'The 50 Best Commercials of All Time,' or 'The 20 Worst-Dressed Celebrities.' Recently, I came across one of these [...]

It sounds simple--eat less fat and carbs, and you'll get lean. But that can't be the whole story, can it? Obviously not--otherwise a lot more of us would be ripped. [...]

IF YOU'RE ONE OF THE MILLIONS of Americans who are currently dieting or are unsuccessfully battling your weight, a unique and newly available supplement shows promise in helping to make [...]

We've seen more profitable and optimistic times in our industry than during the current state of affairs. However, I am confident that if the entire industry gets behind the defense [...]