Pollution and respiratory disease: can diet or supplements help? A review.

Pollution is known to cause and exacerbate a number of chronic respiratory diseases. The World Health Organisation has placed air pollution as the world's largest environmental health risk factor. There has been recent publicity about the role for diet and anti-oxidants in mitigating the effects of pollution, and this review assesses the evidence for alterations in diet, including vitamin supplementation in abrogating the effects of pollution on asthma and other chronic respiratory diseases. We found evidence to suggest that carotenoids, vitamin D and vitamin E help protect against pollution damage which can trigger asthma, COPD and lung cancer initiation. Vitamin C, curcumin, choline and omega-3 fatty acids may also play a role. The Mediterranean diet appears to be of benefit in patients with airways disease and there appears to be a beneficial effect in smokers however there is no direct evidence regarding protecting against air pollution. More studies investigating the effects of nutrition on rapidly rising air pollution are urgently required. However it is very difficult to design such studies due to the confounding factors of diet, obesity, co-morbid illness, medication and environmental exposure.

Vitamin D supplementation in respiratory diseases: evidence from randomized controlled trials.

Pulmonary diseases are one of the most important causes of morbidity and mortality. Although vitamin D is best known for its role in calcium, phosphorus, and bone homeostasis, it has gained attention in the recent years because of a wide range of extraskeletal effects, including its immunomodulatory and antibacterial potential. Vitamin D deficiency is highly prevalent in chronic pulmonary diseases such as chronic obstructive pulmonary disease (COPD), cystic fibrosis, tuberculosis, and asthma, and several clinical studies have been conducted investigating the effect of vitamin D supplementation on disease outcomes. In this review, we searched for positive evidence on vitamin D supplementation from randomized controlled trials and elaborated on the optimal serum vitamin D levels and dosing regimens for an effective intervention. While vitamin D supplementation seems to be beneficial as an add­on treatment for adult patients with asthma and a potent intervention to reduce exacerbations in patients with COPD, there is little evidence for its therapeutic use in cystic fibrosis, pneumonia, and tuberculosis.

[Effects of hypocaloric diet on respiratory manifestations in Willi-Prader syndrome]. / Effets du régime hypocalorique sur les manifestations respiratoires du syndrome de Willi-Prader.

BACKGROUND: Prader-Willi syndrome (PWS) is a multisystem disorder with hyperphagia and obesity. Breathing disorders such as snoring, sleep apnea syndrome, and sleep hypoventilation have also been reported. CASE REPORT: Jonathan was born with the typical features of PWS. He developed exercise dyspnea, cyanosis and nocturnal sweating at the age of 3 years. A few months later, a respiratory failure required his admission to the intensive care unit. His weight was then 48 kg (300% ideal body weight (IBW); physical examination showed polypnea (60 breaths/min), cyanosis, fat deposition on the chest wall. Transcutaneous oxygen saturation was 65%, carbon dioxide tension 81 mmHg (capillary sample). Pulmonary hypertension was found (mean arterial pulmonary pressure = 55 mmHg). Polysomnography detected hypoventilation with persistent hypoxemia increasing during the night and transient dips of oxygen saturation with bradycardia. He was treated with oxygen, mechanical ventilation (facial mask) and a low caloric diet (600 cal/day). Four months later, he weighed 33 kg (200% IBW); the respiratory features had resolved and gazometric values and pulmonary pressure returned to the normal ranges. Polysomnography showed only obstruction apnea and hypopnea without oxygen desaturation. CONCLUSIONS: Patients with PWS may develop respiratory symptoms sufficient by severity to be life threatening. They are related to morbid obesity and are influenced by a hypocaloric diet. Follow-up of patients with this syndrome must include repeated respiratory evaluation.

Assessment of the effects of ascorbic acid on respiratory and alimentary immune reaction

Clinical observation of diseases associated with the occurence of upper respiratory symptoms indicates that clinical features are also present in the alimentary system. Respiratory symptoms occur in consequence of viral or allergic reactions in the respiratory tract, both of which are associated with changes in ascorbic acid metabolism. Alimentary allergic symptoms occur as a rsult of recurrent antigen challenge with specific foods to which patients are sensitive. The specific allergens cause alteration in buccal taste and sensation, and the occurrence of abdominal symptoms. These effects provide sensitive and precise methods for diagnosis of food allergens. Aphthous ulceration has been shown to have a specific allergic basis by challenge of the ulcers with the causative allergens. The pain and inflammation of aphthous ulcers can be completely alleviated by buccal administration of ascorbic acid. The simultaneous occurrence of respiratory and alimentary symptoms following allergenic challenge indicates their common etiology in the allergic syndrome. The beneficial effect of ascorbic acid in the allergic syndrome is discussed. The lay person has a clear definition for himself of the symptoms which make up a cold. For the doctor Tyrell defined a cold as a mild illness in which the main local symptoms are found in the upper respiratory tract and in which nasal symptoms predominate. The early features are produced as a result of primary infection of the nose and nasopharynx by several viruses especially the rhinovirus. Amongst the complications of a cold, however, Macleod only includes sinusitis, eustachian catarrh, and lower respiratory infection. Clinical observation of diseases associated with the occurrence of upper respiratory symptoms indicates that many other features may be present in addition to those occurring in the respiratory tract. The purpose of this paper is to analyse these features, to determine their relationship to each other, and to investigate the effects of administration of supplementary Vitamin C on them. (AU)