Incidence of intolerance to food additives

Amounts of artificial food dyes and added sugars in foods and sweets commonly consumed by children

Artificial food colors (AFCs) are used to color many beverages, foods, and sweets in the United States and throughout the world. In the United States, the Food and Drug Administration (FDA) limits the AFCs allowed in the diet to 9 different colors. The FDA certifies each batch of manufactured AFCs to guarantee purity and safety. The amount certified has risen from 12 mg/capita/d in 1950 to 62 mg/capita/d in 2010. Previously, we reported the amounts of AFCs in commonly consumed beverages. In this article, the amounts of AFCs in commonly consumed foods and sweets are reported. In addition, the amount of sugars in each product is included. Amounts of AFCs reported here along with the beverage data show that many children could be consuming far more dyes than previously thought. Clinical guidance is given to help caregivers avoid AFCs and reduce the amount of sugars in children's diets.

Chronic urticaria--which clinical parameters are pathogenetically relevant? A retrospective investigation of 339 patients

BACKGROUND

Urticaria is a clinical reaction pattern triggered by many factors causing liberation of vasoactive substances such as histamine, prostaglandins and kinins. It presents as transient itching wheals which are either limited to the local stimulus area or more widespread. Urticaria is classified according to its duration into acute (duration > or = 6 weeks) and chronic (duration 6 weeks) forms. Various clinical investigations may be initiated to diagnose the cause. This study critically evaluates the relevance of frequently performed laboratory investigations and searches for infectious foci, as well as the results of physical provocation testing and oral provocation with food additives.

PATIENTS AND METHODS

The laboratory and clinical data of 339 patients who had been treated for urticaria at the Christian-Albrechts-University in Kiel over a period of four years were collected in a data entry form and statistically evaluated. Nominal values were analyzed by their relative and absolute quantities, quantitative parameters with the help of statistical data such as minimum, maximum, median and 25th and 75th percentiles.

RESULTS

Chronic recurrent urticaria was most common, accounting for 52% of cases. Women were affected 1.8 times more often than men. One-third of the patients also had angioedema. The medians of all laboratory parameters evaluated were within normal values. Only rarely were elevated antinuclear antibody titers, abnormal thyroid function tests or active infections such as hepatitis B or borreliosis detected. The search for infectious foci identified tonsillitis or sinusitis in almost 50% of analyzed patients. Positive reactions to physical testing occurred in 30% of patients and in 11% to oral provocation with various food additives.

CONCLUSIONS

This study of a large patient group stresses the relevance of individually-tailored evaluations in patients affected with urticaria rather than an expensive initial broad diagnostic testing. More specific searches should be based on individual clues.

Health effects of salicylates in foods and drugs

There is much (renewed) interest about the effects of salicylates on food intolerance, attention-deficit disorders, and cardiovascular disease. Current evidence for the efficacy of salicylate-elimination diets in the treatment of attention-deficit disorders and hyperactivity is weak, and further investigation is required on the relationship between salicylates and cardiovascular disease.

Prevalence of food allergy and intolerance in the adult Dutch population

The prevalence of food allergy and intolerance (FA/FI) was studied in a random sample (n = 1483) of the Dutch adult population. First, the self-reported FA/FI reactions were investigated by questionnaire. Subsequently, in a clinical follow-up study, it was determined in how many cases this self-reported FA/FI could be objectively confirmed by double-blind placebo-controlled food challenge. More than 10% of the population (12.4%) reported FA/FI to specific food(s). Of the 144 subjects potentially available for the clinical follow-up study, 73 completed the whole protocol. In 12 subjects FA/FI could be confirmed by double-blind placebo-controlled food challenge. This indicates a minimum prevalence of FA/FI in the population of 0.8% (12 of 1483). Assuming that FA/FI is equal among participants, nonparticipants, and dropouts, the prevalence of FA/FI in the Dutch adult population is estimated to be 2.4%. The food (ingredients) involved included pork, white wine, and menthol. Two persons reacted to additives. In three persons glucose intolerance was observed. However, these specific intolerances probably do not reflect the distribution in the general population because the study population formed an extremely heterogeneous group, both with regard to the offending foods and the symptoms. The majority of the subjects had no serious complaints that required medical advice. We conclude that there is a gap between self-reported FA/FI and FA/FI that can be objectively confirmed by double-blind placebo-controlled food challenge.

Adverse reactions to food additives in children with atopic symptoms

In a multicenter study conducted at four Danish hospital pediatric departments, the parents of 472 consecutive children were informed of this project to determine the incidence of intolerance of food additives among children referred to an allergy clinic with symptoms of asthma, atopic dermatitis, rhinitis, or urticaria. After a 2-week period on an additive-free diet, the children were challenged with the eliminated additives. The food additives investigated were coloring agents, preservatives, citric acid, and flavoring agents. Carbonated "lemonade" containing the dissolved additives was used for the open challenge. Two doses were used: a low dose and a 10-fold higher dose. Gelatin capsules were used for a double-blind challenge. The children were 4-15 years old, and they were attending an outpatient pediatric clinic for the first time. Of the 379 patients who entered the study, 44 were excluded and 335 were subjected to open challenge. A total of 23 children developed positive reactions after the open challenge. Sixteen of these patients accepted the double-blind challenge, and six showed a positive reaction to preservatives (atopic dermatitis, asthma, rhinitis), coloring agents (atopic dermatitis, asthma, urticaria, gastrointestinal symptoms), and citric acid (atopic dermatitis, gastrointestinal symptoms). The incidence of intolerance of food additives was 2% (6/335), as based on the double-blind challenge, and 7% (23/335), as based on the open challenge with lemonade. Children with atopic skin symptoms had a statistically increased risk of a positive reaction. This may have consequences for the future clinical investigation of children with atopic cutaneous symptoms.

Immunological aspects of toxicology: premises not promises

The immune system is gaining increasing attention as a target of toxicant action. Many compounds, including metals, drugs, and pesticides, are able to alter immune functions. Additionally, the ability of toxicants to experimentally alter resistance to a variety of bacterial, viral, and tumor challenges is suggestive for the possible involvement of toxicants in morbidity and mortality. However, the implications of immunotoxicology as a subject of study may not be fully realized in some laboratories due to unfamiliarities into the workings of immunity by toxicologists. In an attempt to bridge this toxicology-immunology gap, this paper presents the major concepts of the immune system by reviewing specific examples of immune responses and their environmental interactions. Data from selected toxins are then used to illustrate how these responses may be altered.

Effects of diet and nutrition on drug therapy

Foods containing biochemically active substances have been used therapeutically throughout the ages and continue to function as important adjuncts to drug therapy. But naturally-occurring substances can also have adverse effects, as can the food additives of today. Food--drug interactions can alter the effect of therapeutic agents or cause adverse reactions where none had existed. These problems are often aggravated in elderly patients, who may suffer from malnutrition (e.g., protein insufficiency) or altered food metabolism. Malnutrition in the elderly can be caused by disease, socioeconomic factors, or simply by the deterioration of eating habits. Although nutritional requirements decrease with age, the elderly still need nutrients for the repair of normal structures and for energy. The nutritional needs of the elderly remain poorly defined. Drugs can alter food metabolism, which, in turn, can affect drug action. Many food--drug interactions are well documented; drug absorption and drug elimination are often affected by an altered food metabolism. Particular problems include salicylate-induced iron deficiency, poor monitoring of vitamin metabolism and the effects of vitamin underuse and overuse, and lack of knowledge about the effects of long-term drug use on vitamin metabolism. An additional problem is the presence of potentially harmful materials in non-prescription products.