Since the earliest times, humans have needed to be sensitive to their surroundings to survive, which means that we have an innate awareness of our environment and seek out environments with certain qualities.
First of all, humans have a strong need for safety and security and look for those attributes in their environment. We also look for physical comfort, such as an environment with the right temperature. In addition, we seek an environment that is psychologically comfortable: for example, environments that are familiar, but offer the right amount of stimulus.
Retailers and the hospitality industry know this very well and try to provide an atmosphere that creates a positive customer experience and offers three important attributes: comfort, safety, and entertainment. These attributes are equally important in healthcare as well.
Below are just a few examples of how the environment can impact you.
Perhaps most importantly for health, the environment can create or reduce stress, which in turn impacts our bodies in multiple ways. This is because our brain and our nervous, endocrine, and immune systems are constantly interacting. As neuroscientist Candice Pert puts it, "What you are thinking at any moment is changing your biochemistry."
Thus, the stress of a noisy, confusing hospital room might result in a patient not only feeling worried, sad, or helpless, but experiencing higher blood pressure, heart rate, and muscle tension. In addition, hormones released in response to the emotional stress could suppress the patient's immune system, causing his wounds to heal more slowly.
Stress is an important medical consideration, and creating an environment that reduces stress is a key piece of improving health outcomes.
For more information on stress and how it impacts the body, see Mind-Body Therapies .
There is a great deal of very rigorous research that links the physical environment of hospitals to health outcomes. According to Ulrich and Zimming, authors of the 2004 report, The Role of the Physical Environment in the 21st Century Hospital , there are more than 600 credible studies that show how aspects of healthcare design can influence medical outcomes.
Essentially, this research shows that the conventional ways hospitals have been designed contribute to stress and adverse patient and staff outcomes. Poor design can adversely impact health and wellbeing , as well as staff productivity and ability to deliver great patient care. For example, because of poor design, nurses in most hospitals spend a great deal of time just gathering the material they need for care. One study showed that almost one-third of nursing staff time was spent walking. (Ulrich, p5.)
On the other hand, improving the physical environment can make healthcare settings less stressful, safer, and better places to work.
Experts in the new area of evidence-based design have identified five environmental attributes that can have a large impact on health outcomes. The research demonstrates that improvement in these areas reduces stress and improves patient outcomes:
Changes in these areas help create a healing environment  that is psychologically supportive for patients, families, and staff. And many hospitals and healthcare settings are applying these findings. To find out how, see the section: What Is Happening in Healthcare Settings Today? 
If you want to learn more about how design can impact the environment, see Are There Design Rules to Follow?