If you are facing significant, chronic stress, you may be amazed at the healing power of foods high in omega-3 fatty acids. These include salmon, albacore tuna, walnuts and flaxseed — even fish oil supplements. Research shows that omega-3 fatty acids can reduce the volume of cortisol that your body produces..
In addition, foods high in folic acid, such as leafy greens, and foods high in vitamin B12, such as lean animal protein, can help regulate your mood and increase performance, says Amy Jamieson-Petonic, MEd, a registered dietitian and the director of wellness coaching at the Cleveland Clinic. Folic acid makes dopamine, a neurotransmitter associated with pleasure, while B12 helps form GABA, a neurotransmitter that may help calm you down.
As far as caffeine goes, it can help improve concentration, but too much caffeine can result in a poor night’s sleep, which will only increase your stress. The same goes for alcohol: While it may help relax you when you’re stressed, the fitful night of sleep that will result will just equal more stress. So go easy on both caffeine and alcohol.
"Someone with a healthy and balanced diet is likely to be far less stressed than someone with a poor diet." Stress Management Society