Food allergy reactions range from mild to life-threatening, depending on a person's level of sensitivity. Allergy occurs in people with genetic predisposition to certain sensitivities that can flare up at any point of their life. The immune systems may take years to become sensitive to an allergen, but when it does, it may reach to it without warning.
Stress, changes in lifestyle, a cleaner environment and changes in the body's hormonal balance are thought to be the main triggers of adult allergy. New thinking is including hormones as triggers - women are more likely to develop allergies at puberty, after pregnancy and at menopause - as also stress, which impacts the hormones.
People with allergies have three times the risk of developing asthma, and are also more prone to ear infections and chronic sinusitis.
Warning signs of a milder allergic reaction to food include:
A tight feeling in the throat, or a hoarse voice.
Coughing and wheezing
Nausea, vomiting or stomach pain.
Hives or skin rash.
A tingling sensation on the lips or tongue.
In serious cases, food allergy may cause a severe reaction called anaphylaxis, used to describe suddenly narrowed airways, fall in blood pressure and swollen tongue. This is a life-threatening emergency and the person should be rushed to a hospital.