Query: Artificial Food Colors and ADHD

Relevant passages:
Brain cancer associated with environmental lead exposure: evidence from implementation of a National Petrol-Lead Phase-Out Program (PLPOP) in Taiwa... <=SEP=> BACKGROUND AND OBJECTIVE: In 1981, a Petrol-Lead Phase-Out Program (PLPOP) was launched in Taiwan for the abatement of environmental lead emissions. The present study was intended to examine whether the high Petrol-Lead Emission Areas (PLEA) would result in an increase in the incidence rate of brain cancer based on a national data bank. METHODS: The national brain cancer incidence data was obtained from the Taiwan National Cancer Registry. Age standardized incidence rates were calculated based on the 2000 WHO world standard population, and gasoline consumption data was obtained from the Bureau of Energy. The differences in the trend tests for age-standardized incidence rates of brain cancer between high, median, low, and small PLEA were analyzed. RESULTS: A significant increase was found from small to high PLEA in age-standardized incidence rates of brain cancer. By taking six possible confounders into account, the age-standardized incidence rates for brain cancer were highly correlated with the median and high PLEA by reference to the small PLEA. CONCLUSION: After being adjusted for a number of relevant confounders, it could be concluded that high PLEA might result in an increase in the incidence rate of brain cancer resulting from high lead exposures. Copyright © 2011 Elsevier Ltd. All rights reserved.

The urban rise and fall of air lead (Pb) and the latent surge and retreat of societal violence. <=SEP=> We evaluate air Pb emissions and latent aggravated assault behavior at the scale of the city. We accomplish this by regressing annual Federal Bureau of Investigation aggravated assault rate records against the rise and fall of annual vehicle Pb emissions in Chicago (Illinois), Indianapolis (Indiana), Minneapolis (Minnesota), San Diego (California), Atlanta (Georgia), and New Orleans (Louisiana). Other things held equal, a 1% increase in tonnages of air Pb released 22 years prior raises the present period aggravated assault rate by 0.46% (95% CI, 0.28 to 0.64). Overall our model explains 90% of the variation in aggravated assault across the cities examined. In the case of New Orleans, 85% of temporal variation in the aggravated assault rate is explained by the annual rise and fall of air Pb (total=10,179 metric tons) released on the population of New Orleans 22 years earlier. For every metric ton of Pb released 22 years prior, a latent increase of 1.59 (95% CI, 1.36 to 1.83, p<0.001) aggravated assaults per 100,000 were reported. Vehicles consuming fuel containing Pb additives contributed much larger quantities of Pb dust than generally recognized. Our findings along with others predict that prevention of children's lead exposure from lead dust now will realize numerous societal benefits two decades into the future, including lower rates of aggravated assault. Copyright © 2012 Elsevier Ltd. All rights reserved.

Artificial food dyes and attention deficit hyperactivity disorder. <=SEP=> Attention deficit hyperactivity disorder (ADHD) is one of the most common behavioral disorders in children. Symptoms of ADHD include hyperactivity, low frustration tolerance, impulsivity, and inattention. While the biological pathways leading to ADHD are not clearly delineated, a number of genetic and environmental risk factors for the disorder are recognized. In the early 1970s, research conducted by Dr. Benjamin Feingold found that when hyperactive children were given a diet free of artificial food additives and dyes, symptoms of hyperactivity were reduced. While some clinical studies supported these findings, more rigorous empirical studies conducted over the next 20 years were less positive. As a result, research on the role of food additives in contributing to ADHD waned. In recent years, however, interest in this area has revived. In response to more recent research and public petitions, in December 2009 the British government requested that food manufacturers remove most artificial food dyes from their products. While these strictures could have positive effects on behavior, the removal of food dyes is not a panacea for ADHD, which is a multifaceted disorder with both biological and environmental underpinnings. © 2011 International Life Sciences Institute.

Synthetic Food Colors and Neurobehavioral Hazards: The View from Environmental Health Research <=SEP=> Background: The proposition that synthetic food colors can induce adverse behavioral effects in children was first enunciated in 1975 by Feingold [Why Your Child Is Hyperactive. New York:Random House (1975)], who asserted that elevated sensitivity to food additives underlies the signs of hyperactivity observed in some children. Although the evidence suggested that some unknown proportion of children did respond to synthetic food colors, the U.S. Food and Drug Administration (FDA) interpreted the evidence as inconclusive. A study published in 2007 [McCann et al. Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: a randomised, double-blinded, placebo-controlled trial. Lancet 370:1560–1567 (2007)] drew renewed attention to the hypothesis because of the study’s size and scope. It led the FDA to review the evidence, hold a public hearing, and seek the advice of its Food Advisory Committee. In preparation for the hearing, the FDA reviewed the available evidence and concluded that it did not warrant further agency action. Objectives: In this commentary I examine the basis of the FDA’s position, the elements of the review that led to its decision and that of the Food Advisory Committee, and the reasons that this is an environmental health issue. Discussion: The FDA review confined itself, in essence, to the clinical diagnosis of hyperactivity, as did the charge to the committee, rather than asking the broader environmental question of behavioral effects in the general population; it failed to recognize the significance of vulnerable subpopulations; and it misinterpreted the meaning of effect size as a criterion of risk. The FDA’s response would have benefited from adopting the viewpoints and perspectives common to environmental health research. At the same time, the food color debate offers a lesson to environmental health researchers; namely, too narrow a focus on a single outcome or criterion can be misleading.

Dietary sensitivities and ADHD symptoms: thirty-five years of research. <=SEP=> Artificial food colors (AFCs) have not been established as the main cause of attention-deficit hyperactivity disorder (ADHD), but accumulated evidence suggests that a subgroup shows significant symptom improvement when consuming an AFC-free diet and reacts with ADHD-type symptoms on challenge with AFCs. Of children with suspected sensitivities, 65% to 89% reacted when challenged with at least 100 mg of AFC. Oligoantigenic diet studies suggested that some children in addition to being sensitive to AFCs are also sensitive to common nonsalicylate foods (milk, chocolate, soy, eggs, wheat, corn, legumes) as well as salicylate-containing grapes, tomatoes, and orange. Some studies found "cosensitivity" to be more the rule than the exception. Recently, 2 large studies demonstrated behavioral sensitivity to AFCs and benzoate in children both with and without ADHD. A trial elimination diet is appropriate for children who have not responded satisfactorily to conventional treatment or whose parents wish to pursue a dietary investigation.

Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: a randomised, double-blinded, placebo-controlled... <=SEP=> BACKGROUND: We undertook a randomised, double-blinded, placebo-controlled, crossover trial to test whether intake of artificial food colour and additives (AFCA) affected childhood behaviour. METHODS: 153 3-year-old and 144 8/9-year-old children were included in the study. The challenge drink contained sodium benzoate and one of two AFCA mixes (A or B) or a placebo mix. The main outcome measure was a global hyperactivity aggregate (GHA), based on aggregated z-scores of observed behaviours and ratings by teachers and parents, plus, for 8/9-year-old children, a computerised test of attention. This clinical trial is registered with Current Controlled Trials (registration number ISRCTN74481308). Analysis was per protocol. FINDINGS: 16 3-year-old children and 14 8/9-year-old children did not complete the study, for reasons unrelated to childhood behaviour. Mix A had a significantly adverse effect compared with placebo in GHA for all 3-year-old children (effect size 0.20 [95% CI 0.01-0.39], p=0.044) but not mix B versus placebo. This result persisted when analysis was restricted to 3-year-old children who consumed more than 85% of juice and had no missing data (0.32 [0.05-0.60], p=0.02). 8/9-year-old children showed a significantly adverse effect when given mix A (0.12 [0.02-0.23], p=0.023) or mix B (0.17 [0.07-0.28], p=0.001) when analysis was restricted to those children consuming at least 85% of drinks with no missing data. INTERPRETATION: Artificial colours or a sodium benzoate preservative (or both) in the diet result in increased hyperactivity in 3-year-old and 8/9-year-old children in the general population.

Hiding vegetables to reduce energy density: an effective strategy to increase children's vegetable intake and reduce energy intake <=SEP=> Background: Strategies are needed to increase children's intake of a variety of vegetables, including vegetables that are not well liked. Objective: We investigated whether incorporating puréed vegetables into entrées to reduce the energy density (ED; in kcal/g) affected vegetable and energy intake over 1 d in preschool children. Design: In this crossover study, 3- to 5-y-old children (n = 40) were served all meals and snacks 1 d/wk for 3 wk. Across conditions, entrées at breakfast, lunch, dinner, and evening snack were reduced in ED by increasing the proportion of puréed vegetables. The conditions were 100% ED (standard), 85% ED (tripled vegetable content), and 75% ED (quadrupled vegetable content). Entrées were served with unmanipulated side dishes and snacks, and children were instructed to eat as much as they liked. Results: The daily vegetable intake increased significantly by 52 g (50%) in the 85% ED condition and by 73 g (73%) in the 75% ED condition compared with that in the standard condition (both P < 0.0001). The consumption of more vegetables in entrées did not affect the consumption of the vegetable side dishes. Children ate similar weights of food across conditions; thus, the daily energy intake decreased by 142 kcal (12%) from the 100% to 75% ED conditions (P < 0.05). Children rated their liking of manipulated foods similarly across ED amounts. Conclusion: The incorporation of substantial amounts of puréed vegetables to reduce the ED of foods is an effective strategy to increase the daily vegetable intake and decrease the energy intake in young children. This trial was registered at clinicaltrials.gov as NCT01252433.

Serving styles of raw snack vegetables. What do children want? <=SEP=> The primary aim of this study was to investigate how serving styles of snack vegetables appeal to children, focusing on size and shape. A secondary aim was to investigate children's willingness to participate in fruit and vegetable subscription services at school, and how these could be designed. One hundred and thirty eight children aged 9-12 years indicated their liking for a snack meal comprising a combination of carrots, cucumber, and red pepper. The meal was presented in eight different serving styles: two sizes; small and ordinary, and four shapes; whole/chunk, slices, sticks, and figures (stars). Furthermore, children indicated their willingness to participate in vegetable subscription services, and answered specific questions on how they wanted such servings to be designed (including choice of stimuli and details regarding presentation style). Shape was very influential; children clearly preferred having their vegetables cut. Figures were liked the most, whereas no differences were observed between slices and sticks. Size only mattered for the whole/chunk, where the ordinary size was preferred. Children expressed high willingness to participate in vegetable subscription services. In conclusion, cutting vegetables in shapes children like can relatively easy be done by parents and producers alike, and children seem very interested in receiving such servings during school. Copyright © 2012 Elsevier Ltd. All rights reserved.

Hidden vegetables: an effective strategy to reduce energy intake and increase vegetable intake in adults <=SEP=> Background: The overconsumption of energy-dense foods leads to excessive energy intakes. The substitution of low-energy-dense vegetables for foods higher in energy density can help decrease energy intakes but may be difficult to implement if individuals dislike the taste of vegetables. Objective: We investigated whether incorporating puréed vegetables to decrease the energy density of entrées at multiple meals reduced daily energy intakes and increased daily vegetable intakes. Design: In this crossover study, 20 men and 21 women ate ad libitum breakfast, lunch, and dinner in the laboratory once a week for 3 wk. Across conditions, entrées at meals varied in energy density from standard versions (100% condition) to reduced versions (85% and 75% conditions) by the covert incorporation of 3 or 4.5 times the amount of puréed vegetables. Entrées were accompanied by unmanipulated side dishes. Participants rated their hunger and fullness before and after meals. Results: Subjects consumed a consistent weight of foods across conditions of energy density; thus, the daily energy intake significantly decreased by 202 ± 60 kcal in the 85% condition (P < 0.001) and by 357 ± 47 kcal in the 75% condition (P < 0.0001). Daily vegetable consumption significantly increased from 270 ± 17 g of vegetables in the 100% condition to 487 ± 25 g of vegetables in the 75% condition (P < 0.0001). Despite the decreased energy intake, ratings of hunger and fullness did not significantly differ across conditions. Entrées were rated as similar in palatability across conditions. Conclusions: Large amounts of puréed vegetables can be incorporated into various foods to decrease the energy density. This strategy can lead to substantial reductions in energy intakes and increases in vegetable intakes. This trial was registered at clinicaltrials.gov as NCT01165086.

Associations of parenting styles, parental feeding practices and child characteristics with young children's fruit and vegetable consumption. <=SEP=> The purpose of this study was to investigate the role of parent and child characteristics in explaining children's fruit and vegetable intakes. In 2008, parents of preschoolers (mean age 3.5 years) from 56 schools in Belgium-Flanders completed questionnaires including a parent and child fruit and vegetable food frequency questionnaire, general parenting styles (laxness, overreactivity and positive interactions), specific food parenting practices (child-centered and parent-centered feeding practices) and children's characteristics (children's shyness, emotionality, stubbornness, activity, sociability, and negative reactions to food). Multiple linear regression analyses (n = 755) indicated a significant positive association between children's fruit and vegetable intake and parent's intake and a negative association with children's negative reactions to food. No general parenting style dimension or child personality characteristic explained differences in children's fruit and vegetable intakes. Child-centered feeding practices were positively related to children's fruit and vegetable intakes, while parent-centered feeding practices were negatively related to children's vegetable intakes. In order to try to increase children's fruit and vegetable consumption, parents should be guided to improve their own diet and to use child-centered parenting practices and strategies known to decrease negative reactions to food. Copyright © 2010 Elsevier Ltd. All rights reserved.

The Influence of Social Involvement, Neighborhood Aesthetics, and Community Garden Participation on Fruit and Vegetable Consumption <=SEP=> Objectives. We considered the relationship between an urban adult population's fruit and vegetable consumption and several selected social and psychological processes, beneficial aesthetic experiences, and garden participation. Methods. We conducted a population-based survey representing 436 residents across 58 block groups in Denver, Colorado, from 2006 to 2007. We used multilevel statistical models to evaluate the survey data. Results. Neighborhood aesthetics, social involvement, and community garden participation were significantly associated with fruit and vegetable intake. Community gardeners consumed fruits and vegetables 5.7 times per day, compared with home gardeners (4.6 times per day) and nongardeners (3.9 times per day). Moreover, 56% of community gardeners met national recommendations to consume fruits and vegetables at least 5 times per day, compared with 37% of home gardeners and 25% of nongardeners. Conclusions. Our study results shed light on neighborhood processes that affect food-related behaviors and provides insights about the potential of community gardens to affect these behaviors. The qualities intrinsic to community gardens make them a unique intervention that can narrow the divide between people and the places where food is grown and increase local opportunities to eat better.

Attractive names sustain increased vegetable intake in schools. <=SEP=> OBJECTIVE: This study will determine if the selective use of attractive names can be a sustainable, scalable means to increase the selection of vegetables in school lunchrooms. METHODS: Study 1 paired an attractive name with carrots in five elementary schools (n=147) and measured selection and consumption over a week compared to controls. Study 2 tracked food sales of vegetables in two elementary schools (n=1017) that were systematically attractively named or not named over a two-month period. Both studies were conducted in New York in 2011. RESULTS: Study 1 found that elementary students ate twice the percentage of their carrots if attractively named as "X-ray Vision Carrots," than if un-named or generically named as the "Food of the Day." Study 2 found that elementary school students were 16% more likely to persistently choose more hot vegetable dishes (p<0.001) when they were given fun or attractive names. DISCUSSION: Attractive names effectively and persistently increased healthy food consumption in elementary schools. The scalability of this is underscored by the success of Study 2, which was implemented and executed for negligible cost by a high school student volunteer. Copyright © 2012 Elsevier Inc. All rights reserved.

Classroom "cupcake" celebrations: observations of foods offered and consumed. <=SEP=> OBJECTIVE: To describe food and beverage types offered and consumed during classroom celebrations at an elementary school in a low-income, urban community. In addition, to report student intake of fresh fruit provided alongside other party foods. METHODS: Observations held during 4 classroom celebrations. Food and beverage items were measured and counted before and after each celebration. Consumption data were recorded in aggregate for the entire classroom and later adjusted to mean intake per student. RESULTS: Majority of items offered were low-nutrient, energy-dense foods. Mean caloric intake during celebrations ranged from 259 to 455 cal. Fruit provided during 2 of the 4 classroom celebrations resulted in a mean intake of 1 full serving per student. CONCLUSIONS AND IMPLICATIONS: Caloric intake from low-nutrient, energy-dense foods and beverages offered during classroom celebrations contributed 20% or more of daily caloric needs. However, fresh fruit may be a reasonable addition to the party food table. Copyright © 2012 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

"Split them!" smaller item sizes of cookies lead to a decrease in energy intake in children. <=SEP=> OBJECTIVE: Examine the influence of altering the size of snack food (ie, small vs large cookies) on short-term energy intake. METHODS: First- and sixth-graders (n = 77) participated in a between-subjects experimental design. All participants were offered the same gram weight of cookies during an afternoon tea at their school. For half of the participants, food was cut in 2 to make the small item size. Food intake (number of cookies, gram weight, and energy intake) was examined using ANOVA. RESULTS: Decreasing the item size of food led to a decrease of 25% in gram weight intake, corresponding to 68 kcal. Appetitive ratings and subject and food characteristics had no moderating effect. CONCLUSIONS AND IMPLICATIONS: Reducing the item size of food could prove a useful dietary prevention strategy based on decreased consumption, aimed at countering obesity-promoting eating behaviors favored by the easy availability of large food portions. Copyright © 2012 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

Offering “dip” promotes intake of a moderately-liked raw vegetable among preschoolers with genetic sensitivity to bitterness. <=SEP=> BACKGROUND: Evidence-based strategies for promoting vegetable consumption among children are limited. OBJECTIVE: To determine the effects of providing a palatable “dip” along with repeated exposure to a raw vegetable on preschoolers' liking and intake. PARTICIPANTS: One hundred fifty-two predominately Hispanic preschool-aged children studied in Head Start classrooms in 2008. DESIGN: A between-subjects, quasiexperimental design was used. A moderately-liked raw vegetable (broccoli) was offered twice weekly at afternoon snacks for 7 weeks. Classrooms were randomized to receive broccoli in one of four conditions differing in the provision of dip. Bitter taste sensitivity was assessed using 6-n-propylthiouracil. INTERVENTION: Broccoli was provided in four conditions: with regular salad dressing as a dip, with a light (reduced energy/fat) version of the dressing as a dip, mixed with the regular dressing as a sauce, or plain (without dressing). MAIN OUTCOME MEASURES: Mean broccoli intake during 7 weeks of exposure and broccoli liking following exposure. STATISTICAL ANALYSES: Descriptive statistics were generated. Multilevel models for repeated measures tested effects of condition and bitter sensitivity on mean broccoli intake during exposure and on pre- and post-exposure liking while adjusting for classroom effects and potential covariates. RESULTS: The majority of Hispanic preschoolers (70%) showed sensitivity to the bitter taste of 6-n-propylthiouracil. Children's broccoli liking increased following exposure but did not vary by dip condition or bitter sensitivity. Bitter-sensitive children, however, ate 80% more broccoli with dressing than when served plain (P<0.001); effects did vary based on whether regular or light dressing was provided as a dip or sauce. Dip did not promote broccoli intake among bitter-insensitive children. CONCLUSIONS: Providing dip—regular, light, or as a sauce—increased raw broccoli intake among bitter-sensitive Hispanic preschoolers. Findings suggest that offering low-fat dips can promote vegetable intake among some children who are sensitive to bitter tastes.

Popcorn-worker lung caused by corporate and regulatory negligence: an avoidable tragedy. <=SEP=> Diacetyl-containing butter flavor was identified as the cause of an outbreak of bronchiolitis obliterans (BO) and other lung diseases in popcorn-plant workers. Litigation documents show that the outbreak was both predictable and preventable. The industry trade organization was aware of BO cases in workers at butter-flavoring and popcorn-manufacturing plants but often failed to implement industrial hygiene improvements and actively hid pertinent warning information. Due to weaknesses in the organization and mandates of regulatory bodies, organizations such as NIOSH, OSHA, the FDA, particularly the "generally recognized as safe" (GRAS) system, and the EPA failed to detect and prevent the outbreak, which highlights the need for systemic changes in food-product regulation, including the need for corporations to act responsibly, for stronger regulations with active enforcement, for a restructuring of the GRAS system, and for criminal penalties against corporations and professionals who knowingly hide information relevant to worker protection.

Bronchiolitis obliterans organizing pneumonia (BOOP) after thoracic radiotherapy for breast carcinoma <=SEP=> Common complications of thoracic radiotherapy include esophagitis and radiation pneumonitis. However, it is important to be aware of uncommon post-radiotherapy complications such as bronchiolitis obliterans organizing pneumonia (BOOP). We report on two patients with carcinoma of the breast who developed an interstitial lung disease consistent with BOOP. BOOP responds to treatment with corticosteroids and the prognosis is generally good despite of the need for long-term administration of corticosteroids as relapses can occur during tapering of steroids. This report provides guidelines for the evaluation and treatment of patients with pulmonary infiltrates after radiotherapy.

Bronchiolitis obliterans and consumer exposure to butter-flavored microwave popcorn: a case series. <=SEP=> Respiratory exposure to diacetyl and diacetyl-containing flavorings used in butter-flavored microwave popcorn (BFMP) causes lung disease, including bronchiolitis obliterans (BO), in flavorings and popcorn manufacturing workers. However, there are no published reports of lung disease among BFMP consumers. We present a case series of three BFMP consumers with biopsy-confirmed BO. We review data relating to consumer exposures, estimate case exposures, and compare them to diacetyl-containing flavoring-exposed manufacturing workers with lung disease. These consumer cases' exposure levels are comparable to those that caused disease in workers. We were unable to identify any other exposures or diseases known or suspected to cause BO in these cases. BFMP poses a significant respiratory risk to consumers. Some manufacturers have substituted diacetyl with other alpha-diketones that are likely to pose a similar risk. Simple consumer practices such as cooling the popcorn bag would eliminate the risk of severe lung disease.

Algal-oil capsules and cooked salmon: nutritionally equivalent sources of docosahexaenoic acid. <=SEP=> Food and nutrition professionals question whether supplement-sourced nutrients appear to be equivalent to those derived from natural food sources. We compared the nutritional availability of docosahexaenoic acid (DHA) from algal-oil capsules to that from assayed cooked salmon in 32 healthy men and women, ages 20 to 65 years, in a randomized, open-label, parallel-group study. In this 2-week study comparing 600 mg DHA/day from algal-oil capsules to that from assayed portions of cooked salmon, mean change from baseline in plasma phospholipids and erythrocyte DHA levels was analyzed and DHA levels were compared by Student's t tests. In post-hoc analyses to determine bioequivalence, least-squares mean ratios of percent change from baseline in plasma phospholipid and erythrocyte DHA levels were compared. DHA levels increased by approximately 80% in plasma phospholipids and by approximately 25% in erythrocytes in both groups. Changes in DHA levels in plasma phospholipids and erythrocytes were similar between groups. As measured by delivery of DHA to both plasma and erythrocytes, fish and algal-oil capsules were equivalent. Both regimens were generally well-tolerated. These results indicate that algal-oil DHA capsules and cooked salmon appear to be bioequivalent in providing DHA to plasma and red blood cells and, accordingly, that algal-oil DHA capsules represent a safe and convenient source of non-fish-derived DHA.

Aquaculture practices and potential human health risks: current knowledge and future priorities. <=SEP=> Annual global aquaculture production has more than tripled within the past 15 years, and by 2015, aquaculture is predicted to account for 39% of total global seafood production by weight. Given that lack of adequate nutrition is a leading contributor to the global burden of disease, increased food production through aquaculture is a seemingly welcome sign. However, as production surges, aquaculture facilities increasingly rely on the heavy input of formulated feeds, antibiotics, antifungals, and agrochemicals. This review summarizes our current knowledge concerning major chemical, biological and emerging agents that are employed in modern aquaculture facilities and their potential impacts on public health. Findings from this review indicate that current aquaculture practices can lead to elevated levels of antibiotic residues, antibiotic-resistant bacteria, persistent organic pollutants, metals, parasites, and viruses in aquacultured finfish and shellfish. Specific populations at risk of exposure to these contaminants include individuals working in aquaculture facilities, populations living around these facilities, and consumers of aquacultured food products. Additional research is necessary not only to fully understand the human health risks associated with aquacultured fish versus wild-caught fish but also to develop appropriate interventions that could reduce or prevent these risks. In order to adequately understand, address and prevent these impacts at local, national and global scales, researchers, policy makers, governments, and aquaculture industries must collaborate and cooperate in exchanging critical information and developing targeted policies that are practical, effective and enforceable.

Food additives and hyperactivity <=SEP=> Evidence supports a trial period of eliminating colourings and preservatives from the diet