Clearly state your position in the introduction, for instance, by strongly agreeing that nature is indispensable for well-being. While briefly acknowledging that urbanisation might limit opportunities for some, immediately pivot to assert that its benefits remain universally essential, setting up your main arguments.

Argue for both physical and mental health benefits. For physical health, mention increased physical activity, Vitamin D synthesis, and reduced risk of chronic diseases, citing examples like the 'Blue Zones' where active outdoor lifestyles contribute to longevity. For mental well-being, reference the concept of 'forest bathing' (Shinrin-yoku) from Japan, where immersion in nature is prescribed for stress reduction and improved mood.

A common mistake is discussing general health benefits of exercise without explicitly linking them to the unique aspects of nature or outdoor environments. Avoid this by focusing on elements like fresh air, natural light, varied terrain, biodiversity, and the psychological restorative effects of green spaces, rather than just the physical exertion itself.

Employ transition phrases that clearly signal the progression of your arguments, especially when moving from physical to mental health benefits. For instance, after discussing physical advantages, you could transition with 'Beyond the physiological benefits, the psychological dividends of engaging with nature are equally profound,' ensuring a cohesive flow.

Examiners look for a nuanced understanding of 'essential' – not just 'beneficial' – demonstrated through well-developed arguments supported by specific examples of how nature uniquely contributes to both physical and mental well-being. A band 8-9 response will also showcase sophisticated vocabulary related to environmental psychology and public health, alongside complex grammatical structures used accurately to express subtle distinctions.