Mobile phones and head tumours. The discrepancies in cause-effect relationships in the epidemiological studies - how do they arise?

The uncertainty about the relationship between the use of mobile phones (MPs: analogue and digital cellulars, and cordless) and the increase of head tumour risk can be solved by a critical analysis of the methodological elements of both the positive and the negative studies. Results by Hardell indicate a cause/effect relationship: exposures for or latencies from 65 10 years to MPs increase by up to 100% the risk of tumour on the same side of the head preferred for phone use (ipsilateral tumours) - which is the only one significantly irradiated - with statistical significance for brain gliomas, meningiomas and acoustic neuromas. On the contrary, studies published under the Interphone project and others produced negative results and are characterised by the substantial underestimation of the risk of tumour. However, also in the Interphone studies a clear and statistically significant increase of ipsilateral head tumours (gliomas, neuromas and parotid gland tumours) is quite common in people having used MPs since or for 65 10 years. And also the metaanalyses by Hardell and other Authors, including only the literature data on ipsilateral tumours in people having used MPs since or for 65 10 years - and so also part of the Interphone data - still show statistically significant increases of head tumours

What is hormesis and its relevance to healthy aging and longevity?

This paper provides a broad overview of hormesis, a specific type of biphasic dose response, its historical and scientific foundations as well as its biomedical applications, especially with respect to aging. Hormesis is a fundamental component of adaptability, neutralizing many endogenous and environmental challenges by toxic agents, thereby enhancing survival. Hormesis is highly conserved, broadly generalizable, and pleiotrophic, being independent of biological model, endpoint measured, inducing agent, level of biological organization and mechanism. The low dose stimulatory hormetic response has specific characteristics which defines both the quantitative features of biological plasticity and the potential for maximum biological performance, thereby estimating the limits to which numerous medical and pharmacological interventions may affect humans. The substantial degrading of some hormetic processes in the aged may profoundly reduce the capacity to respond effectively to numerous environmental/ischemic and other stressors leading to compromised health, disease and, ultimately, defining the bounds of longevity