Table 1.

Main lifestyle factors associated to risk of Alzheimer’s disease

Life-style factor	Relevant mechanisms	References
Diet	Diet components such as lipids interfere with brain entrance of insulin/IGF-I.	[74, 75]
	Inflammation and oxidative stress produced by unhealthy diets.	[78, 79]
Physical Activity	Exercise increases brain sensitivity to insulin and stimulates brain uptake of circulating IGF-I.	[68, 122]
Stress	High glucocorticoids elicit insulin/IGF-I resistance.	[144–146]
	Stress reduces brain IGF-I signalling.	Figure 2
Mental Activity	Increased mental activity will increase brain uptake of IGF-I.	[69]
Sleep/Wake Cycle	Insulin modulation of orexin neurons may impact on activity patterns.	[181]