Phyllis J. Stumbo

Effects of Diets High in Sucrose or Aspartame on The Behavior and Cognitive Performance of Children

BACKGROUND Both dietary sucrose and the sweetener aspartame have been reported to produce hyperactivity and other behavioral problems in children. METHODS We conducted a double-blind controlled trial with two groups of children: 25 normal preschool children (3 to 5 years of age), and 23 school-age children (6 to 10 years) described by their parents as sensitive to sugar. The children and their families followed a different diet for each of three consecutive three-week periods. One diet was high in sucrose with no artificial sweeteners, another was low in sucrose and contained aspartame as a sweetener, and the third was low in sucrose and contained saccharin (placebo) as a sweetener. All the diets were essentially free of additives, artificial food coloring, and preservatives. The childrens behavior and cognitive performance were evaluated weekly. RESULTS The preschool children ingested a mean (+/- SD) of 5600 +/- 2100 mg of sucrose per kilogram of body weight per day while on the sucrose diet, 38 +/- 13 mg of aspartame per kilogram per day while on the aspartame diet, and 12 +/- 4.5 mg of saccharin per kilogram per day while on the saccharin diet. The school-age children considered to be sensitive to sugar ingested 4500 +/- 1200 mg of sucrose per kilogram, 32 +/- 8.9 mg of aspartame per kilogram, and 9.9 +/- 3.9 mg of saccharin per kilogram, respectively. For the children described as sugar-sensitive, there were no significant differences among the three diets in any of 39 behavioral and cognitive variables. For the preschool children, only 4 of the 31 measures differed significantly among the three diets, and there was no consistent pattern in the differences that were observed. CONCLUSIONS Even when intake exceeds typical dietary levels, neither dietary sucrose nor aspartame affects childrens behavior or cognitive function.

The dietary intervention study in children (DISC) : dietary assessment methods for 8- to 10-year-olds

OBJECTIVES The dietary assessment methods used in the Dietary Intervention Study in Children (DISC) are described and the rationale, validity, and/or general usefulness of each are discussed. DESIGN DISC is the first multicenter, randomized, clinical trial to study the feasibility and long-term efficacy, safety, and acceptability of a fat-moderately diet in 8- to 10-year-old prepubescent children with moderately elevated plasma low-density lipoprotein cholesterol (LDL-C) levels. Final data collection for the original study (DISC I) occurred December 1, 1993; continued intervention and follow-up (DISC II) will extend beyond 1997. SETTING Six clinical centers across the country participate in DISC. SUBJECTS Preadolescent boys and girls with fasting LDL-C levels between the 80th and 98th age-specific and sex-specific percentiles established by the Lipid Research Clinics were eligible for the study. The feasibility phase included 140 children who were then enveloped into the full-scale trial. Baseline dietary data for 652 randomized children in the full-scale trial and 6-month results for the feasibility cohort are reported. INTERVENTIONS Dietary assessment involved several elements: (a) determining eligibility based on consumption of more than 30% of energy from total fat, (b) monitoring adherence to and adequacy of the intervention diet, (c) evaluating acceptability of the diet in the intervention group, and (d) determining appropriate foods for the intervention diet. Methods are described for each purpose. MAIN OUTCOME MEASURES LDL-C differences between the two groups and differences in total and saturated fat intakes as calculated from three 24-hour recalls were the primary outcome measures. Six-month dietary differences in the feasibility group are reported. STATISTICAL METHODS Baseline group means and 6-month differences in dietary intake are reported for the full-scale trial and feasibility study, respectively. RESULTS Baseline mean intake from three dietary recalls for the intervention (n = 328) and control (n = 324) groups, respectively, were as follows: energy = 1,759 kcal and 1,728 kcal; total energy from fat = 33.3% and 34.0%; total energy from saturated fat = 12.5% and 12.7%; and total dietary cholesterol = 209 mg and 195 mg. After 6 months of intervention, percentage of energy from total fat and saturated fat was reduced by 5.1% (P = .004) and 2.9% (P < .001), respectively, in this feasibility subset (n = 73) of the intervention group. Essentially no change in these parameters occurred in the control group (n = 67), which demonstrates a measurable difference in reporting between groups. APPLICATIONS/CONCLUSIONS Results illustrate the feasibility of implementing a variety of dietary assessment methods among preadolescent children without relying primarily on parental reports.

New technology in dietary assessment: a review of digital methods in improving food record accuracy

Methods for conducting dietary assessment in the United States date back to the early twentieth century. Methods of assessment encompassed dietary records, written and spoken dietary recalls, FFQ using pencil and paper and more recently computer and internet applications. Emerging innovations involve camera and mobile telephone technology to capture food and meal images. This paper describes six projects sponsored by the United States National Institutes of Health that use digital methods to improve food records and two mobile phone applications using crowdsourcing. The techniques under development show promise for improving accuracy of food records.

Is coffee a colonic stimulant

BACKGROUND It is unclear if ingestion of coffee affects colonic function and if this effect is due to its caffeine content. We investigated the effects of coffee on colonic motor activity in healthy humans. METHODS We performed ambulatory colonic manometry by placing a six-sensor solid-state probe up to the mid-transverse colon in 12 healthy subjects. The following day, over a 10 h period, subjects received four stimuli: 240 ml of three drinks at 45 degrees C in random order: black Colombian coffee (150 mg caffeine), decaffeinated coffee or water and 1000 kcal meal. We analyzed the effects of each stimulant on colonic motor responses. RESULTS Caffeinated coffee, decaffeinated coffee and meal induced more activity in the colon with a greater area under the curve of pressure waves (P < 0.01) and a greater number of propagated contractions (P < 0.05) when compared with water. Caffeinated coffee, decaffeinated coffee and meal induced greater (P < 0.05) motor activity in the transverse/descending colon when compared with the rectosigmoid colon. The effects of decaffeinated coffee on colonic motility were not significantly different from those of water or caffeinated coffee and were lower (P < 0.05) than that of a meal. CONCLUSION Caffeinated coffee stimulates colonic motor activity. Its magnitude is similar to a meal, 60% stronger than water and 23% stronger than decaffeinated coffee.

Phenytoin-Folic Acid Interaction

Objective: To review information regarding the dual and interdependent drug-nutrient interaction between phenytoin and folic acid and other literature involving phenytoin and folic acid. Data Sources: Information was retrieved from a MEDLINE search of English-language literature conducted from 1983 (time of the last review) to March 1995. Search terms included folic acid, phenytoin, and folic acid deficiency. Additional references were obtained from Current Contents and from the bibliographies of the retrieved references. Study Selection: All human studies examining the effects of phenytoin on serum folate concentrations and folic acid supplementation on serum phenytoin concentrations were selected. These included studies of patients with epilepsy and healthy volunteers as well as case reports. Case reports were included because of the extensive length of time needed to study this drug interaction. Data Extraction: Data extracted included gender, dosing, serum folate concentrations if available, pharmacokinetics, and adverse events. Data Synthesis: Serum folate decreases when phenytoin therapy is initiated alone with no folate supplementation. Folic acid supplementation in folate-deficient patients with epilepsy changes the pharmacokinetics of phenytoin, usually leading to lower serum phenytoin concentrations and possible seizure breakthrough. Folate is hypothesized to be a cofactor in phenytoin metabolism and may be responsible for the “pseudo-steady-state,” which is a concentration where phenytoin appears to be at steady-state, but in reality, is not. Phenytoin and folic acid therapy initiated concomitantly prevents decreased folate and phenytoin obtains steady-state concentrations sooner. Conclusions: Folic acid supplementation should be initiated each time phenytoin therapy commences because of the hypothesized cofactor mechanism, decreased adverse effects associated with folate deficiency, and better seizure control with no perturbation of phenytoin pharmacokinetics.

Automatic Food Documentation and Volume Computation using Digital Imaging and Electronic Transmission

Capturing accurate food intake data from participants enrolled in nutrition studies is essential for understanding relationships between diet and chronic disease (1). Numerous methods are employed to assess dietary intake such as food records, 24-hour recalls, or food frequency questionnaires. While each of these techniques is valuable, the error associated with each is unique. The food record requires a motivated participant, is tedious for some, places attention on the act of eating thus altering intake and is difficult for subjects with low literacy skills (2). Interviewing subjects about the previous day’s intake avoids the reactivity involved when recording current intake, but also requires the individual reporting intake to have good recall skills, knowledge of food names and ability to estimate amounts eaten; and requires a well-trained interviewer which makes this a costly process (2, 3). Food frequency questionnaires are limited by food lists and lack of detail regarding food preparation, and require respondents to summarize past intake over many months or the past year. Such instruments are known to contain significant measurement error (4). While all these methods provide valuable information about dietary intake, improving methodology even modestly would advance our knowledge about the influence of food intake on health. FIVR (Food Intake Visual and voice Recognizer), a subproject of the Genes, Environment, and Health Initiative from the National Institutes of Health (RFA-CA-07-032 at www.gei.nih.gov/index.asp), is designed to use new digital photographing technology to reduce measurement error associated with a food record. The intent is to create a tool that would both increase accuracy of intake records and reduce the recording burden for respondents. Using a mobile phone with a camera (Figure 1), the participant will photograph foods both before and after eating. In this way initial portion size is recorded as well as portions left uneaten. The photographs would be used to identify both the types and amounts of foods consumed. This paper briefly describes the technology and techniques involved. Figure 1 Typical Mobile Phone Interface showing (a). operator instruction screen, (b) menu of activities available and (c) camera poised to record meal. Creating sufficiently detailed images Capturing images of meals using a mobile phone presents its own unique challenges. Identifying foods from a picture requires a clear image; the automatic calculation of the amount eaten (volume) requires three or more clear images to be taken by the mobile phone user. Since a single image will not support estimation of food volume, rather 3-dimensional objects must be viewed at more than one angle (5, 6). The three images in Figure 2 are captured from 3 slightly different angles. A calibration object is also required in the images for determination of 3-dimensional size (see Figure 2). The calibration object (fiduciary marker) included in the images in Figure 2 is a card with black and white squares of known size. However, a standard credit card can be used to establish the relationship between size in image pixels and actual size of the object in milliliters. Images are also required before and after the meal is eaten to document the volume of food consumed. Figure 2 Three images captured by moving the camera using the FIVR mobile phone system. Quality of the image hinges on several factors including resolution (roughly indicated by number of pixels per image). Higher resolution (more pixels per image) creates larger files, which makes transferring images slower and more subject to failure, thus testing and refinement of the image details is integral to developing a successful system. Camera focus is critical since the best volumetric estimation is obtained when the three images are in focus and taken with the plate at the same distance from the camera. With fixed focus cameras, the images will be blurred if not taken at the right distance (which is often too great). With auto-focus cameras, the focusing is assured but the distance still must be maintained by the user. Ways to adjust the image to correct for small variations in distance are still being explored.

Effect of Vitamin E on Resistance Vessel Endothelial Dysfunction Induced by Methionine

We tested if vitamin E, a fat-soluble antioxidant, prevents resistance vessel endothelial dysfunction caused by methionine-induced hyperhomocysteinemia in humans. Moderate elevations in plasma homocysteine concentrations are associated with atherosclerosis and hypertension. Homocysteine causes endothelial dysfunction possibly through several mechanisms. No previous study has tested if a fat-soluble antioxidant can prevent endothelial dysfunction caused by experimental hyperhomocysteinemia. Ten healthy subjects participated in a 2 x 2 factorial, double-blind crossover study, receiving L-methionine (100 mg/kg at -6 hours) or vehicle, with and without vitamin E (1,200 IU at -13 hours). Endothelial function of forearm resistance vessels was assessed using forearm blood flow responses to brachial artery administration of endothelium-dependent and endothelium-independent agents. Forearm resistance vessel dilatation to acetylcholine was significantly impaired 7 hours after methionine (placebo, 583 +/- 87% vs methionine 30 +/- 68%; p <0.05). Dilatation to bradykinin was also impaired (placebo, 509 +/- 54% vs methionine 289 +/- 48%; p <0.05). Methionine did not alter vasodilatation to the endothelium-independent vasodilators, nitroprusside, and verapamil. Methionine-induced impairment of resistance vessel dilatation to acetylcholine and bradykinin (p <0.05 vs placebo) was prevented by administration of vitamin E (acetylcholine, p = 0.004; bradykinin, p = 0.004; both vs methionine alone). Experimentally increasing plasma homocysteine concentrations by oral methionine rapidly impairs resistance vessel endothelial function in healthy humans and this effect is reversed with administration of the fat-soluble antioxidant, vitamin E.

Resistance vessel endothelial function in healthy humans during transient postprandial hypertriglyceridemia

A single high-fat meal transiently impairs conduit vessel endothelial function. We tested the hypothesis that transient moderate hypertriglyceridemia by consumption of a high-fat meal impairs forearm resistance vessel endothelial function. Fifteen healthy persons consumed isocaloric high- and low-fat meals (900 calories, 50 and 4 g of fat, respectively) on 2 separate days. Endothelial function in forearm resistance vessels was assessed using blood flow responses to local intra-arterial infusion of nitroprusside, acetylcholine, bradykinin, and verapamil from 1 to 3 hours after the meal. Serum triglycerides increased from 112 +/- 15 mg/dl preprandially to 165 +/- 20 mg/dl 4 hours after the high-fat meal, which was a significantly larger increase than levels after the low-fat meal (p = 0.01). Total cholesterol, high-density lipoprotein, low-density lipoprotein, and very low density lipoprotein (VLDL) cholesterol concentrations did not change. There was no difference between high- and low-fat meals in vasodilation to the endothelium-dependent agents acetylcholine (low fat, 337 +/- 47%; high fat, 356 +/- 88%; p = 0.81) and bradykinin (low fat, 312 +/- 39%; high fat, 403 +/- 111%; p = 0.28), or to the endothelium-independent vasodilators nitroprusside (low fat, 313 +/- 27%; high fat, 355 +/- 42%; p = 0.31) and verapamil (low fat, 292 +/- 48%; high fat, 299 +/- 36%; p = 0.18). Thus, transient hypertriglyceridemia due to a high-fat meal does not impair resistance vessel endothelial function. These data contrast with previous studies in conduit vessels that showed substantial endothelial dysfunction. Therefore, although high-fat intake may contribute to large artery atherosclerosis, it probably does not predispose to hypertension or ischemia through resistance vessel dysfunction. The results suggest that the mechanism by which triglyceride-rich lipoproteins impair endothelial function in conduit vessels is not operative in resistance vessels.

Drug and Environmental Factors Associated with Adverse Pregnancy Outcomes Part I: Antiepileptic Drugs, Contraceptives, Smoking, and Folate

OBJECTIVE: Part I of this review examines the relationship between antiepileptic drugs (AEDs) and pregnancy outcomes. Drug-induced folate deficiency and the role of AED metabolism are emphasized. Part II will discuss periconceptional folate supplementation for prevention of birth defects. Part III will discuss the mechanism of folates protective effect, therapeutic recommendations, compliance, and cost. DATA SOURCES: A MEDLINE search was conducted for journal articles published through December 1997. Additional sources were obtained from Current Contents and citations from the references obtained. Search terms included phenytoin, carbamazepine, phenobarbital, primidone, valproic acid, oral contraceptives, clomiphene, drug-induced abnormalities, spina bifida, anencephaly, neural tube defect, folate, folic acid, and folic acid deficiency. STUDY SELECTION: Relevant animal and human studies examining the effects of AEDs, smoking, and oral contraceptives on folate status and pregnancy outcome are reviewed. DATA EXTRACTION: Studies and case reports were interpreted. Data extracted included dosing, serum and red blood cell folate concentrations, teratogenicity of anticonvulsant medications, metabolism of AEDs and folate, and genetic susceptibility to AED-induced teratogenicity. DATA SYNTHESIS: Low serum and red blood cell folate concentrations are associated with adverse pregnancy outcomes. Decreases in serum folate are seen with AEDs, oral contraceptives, and smoking. Since similar birth defects are observed with multiple AEDs, metabolism of aromatic AEDs to epoxide metabolites and genetic factors may play a role in teratogenesis. CONCLUSIONS: Adequate prepregnancy planning is essential for women who have epilepsy. Women receiving folate-lowering drugs may be at increased risk of adverse pregnancy outcomes. Therefore, epileptic women contemplating pregnancy should be treated with the minimum number of folate-lowering drugs possible and receive folic acid supplementation.

Evaluation of Web-Based, Self-Administered, Graphical Food Frequency Questionnaire

Computer-administered food frequency questionnaires (FFQs) can address limitations inherent in paper questionnaires by allowing very complex skip patterns, portion size estimation based on food pictures, and real-time error checking. We evaluated a web-based FFQ, the Graphical Food Frequency System (GraFFS). Participants completed the GraFFS, six telephone-administered 24-hour dietary recalls over the next 12 weeks, followed by a second GraFFS. Participants were 40 men and 34 women, aged 18 to 69 years, living in the Columbus, OH, area. Intakes of energy, macronutrients, and 17 micronutrients/food components were estimated from the GraFFS and the mean of all recalls. Bias (second GraFFS minus recalls) was -9%, -5%, +4%, and -4% for energy and percentages of energy from fat, carbohydrate, and protein, respectively. De-attenuated, energy-adjusted correlations (intermethod reliability) between the recalls and the second GraFFS for fat, carbohydrate, protein, and alcohol were 0.82, 0.79, 0.67, and 0.90, respectively; for micronutrients/food components the median was 0.61 and ranged from 0.40 for zinc to 0.92 for beta carotene. The correlations between the two administrations of the GraFFS (test-retest reliability) for fat, carbohydrate, protein, and alcohol were 0.60, 0.63, 0.73, and 0.87, respectively; among micronutrients/food components the median was 0.67 and ranged from 0.49 for vitamin B-12 to 0.82 for fiber. The measurement characteristics of the GraFFS were at least as good as those reported for most paper FFQs, and its high intermethod reliability suggests that further development of computer-administered FFQs is warranted.