Did you know stress can cause memory problems? And that's not all. Read on for more surprising symptoms and learn techniques to help you beat stress.

We've all had difficult moments in our lives, such as the death of a loved one, a looming deadline or planning a wedding. For some of us, those moments get the better of us and -- argh! -- stress us out. Tension builds along our back, neck and head, we feel completely overwhelmed and we either overeat or don't eat at all.

Some symptoms of stress -- whether cognitive, physical, emotional or behavioural -- are easily recognizable. Others may surprise you.

Here are five surprising stress symptoms:

1. Learning and memory problems
Can't find your car keys while a deadline hangs overhead? When you're under pressure stress is actually beneficial, sharpening your focus and helping you push through.

To do so, however, the stress hormone cortisol down-regulates other system activities, such as memory and learning, in order to mobilize energy and resources from elsewhere in the body until the challenge is over, explains Leslie Atkinson, scientific director of the Institute for Stress and Wellbeing Research at Ryerson University and a professor in the school's Department of Psychology.

Acute short-term stress is OK, but with chronic stress -- that is, "an ongoing sense that the challenges are beyond your capacities" -- cognitive aging is accelerated and parts of the brain (the hippocampus and frontal cortex, in particular) can be damaged.

2. Abdominal weight gain
Once upon a time, our ancestors stored fat as energy reserves to use for fight or flight in times of danger -- for fending off predators or searching for food, for example. "The stress system is part of our evolutionary equipment," explains Atkinson. "It evolved to keep us alive."

Today, stress triggers the same response: the excess secretion of cortisol causes fat to be deposited viscerally rather than peripherally, regardless of whether you're thin or overweight.

3. Poor parenting
Pregnancy and parenthood are nerve-wracking events, for both mother and child. If a mom-to-be is stressed out, her high cortisol prepares her baby in utero for the environment into which he or she will be born by programming the child's hypothalamic-pituitary-adrenal (HPA) axis, which helps regulate stress and release cortisol.

Prenatal maternal stress can have lasting effects on a child's health, immune system and cognitive development, according to the Douglas Mental Health University Institute in Montreal.

"Post-natally, a mother can be a stressor to an infant, so that infant is going to start up-regulating their system because the mother is creating a stressful environment," says Atkinson.

An infant can also be a stressor to the mother, affecting her emotions and executive functions (the ability to plan and to adjust to change), which are essential when rearing a child. If mom is relying on severe parenting techniques (yelling, screaming, hitting) or has become completely lackadaisical and unable to cope, help is needed.

4. Infertility and irregular periods
Stress affects the brain's hypothalamus gland, which is in charge of the hormones that release a woman's eggs. As previously mentioned, when danger is imminent the body diverts its energies to fight or flight and will worry about menstruation and ovulation when things have calmed down.

"The stress system is designed for immediate action," says Atkinson. "Periods and reproduction are important, but not in the immediate term."

5. Stomach and intestinal difficulties
From butterflies in the belly to gut-wrenching decisions, the stomach and brain are so closely linked that stress impacts the physiology of the gut. Potential issues include intestinal infection, gastric ulcers, gastroesophageal reflux disease, irritable bowel syndrome and food allergies, not to mention continuous stomachaches.

According to a Harvard Medical School report, stress can make the pain of gastrointestinal (GI) disorders feel even worse. Although not all GI disorders are related to stress, the report goes on to say that a review of 13 studies has shown that patients who tried psychological-based therapies improved more than those who were treated conventionally.

Stressed out -- so what?
Acute stress is common, beatable and even useful. The self-regulating HPA axis simply secretes enough cortisol to combat the threat and then the system shuts itself down. However, the more stressors you face the more sensitive you can become.

"Stress can lead to more stress," explains Atkinson. Reactions turn more frequent and intense, and often occur around more trivial issues. If your physiological response is activated for the long term, the system breaks down, cortisol is continually secreted and real damage can be done.

"Stress and stress physiology are involved in every disease process, from the common cold to cancer," says Atkinson.

What can I do to beat stress and its symptoms?

"You're going to want to address the symptoms, but you're also going to want to deal with the stress," explains Atkinson. "You don't want to mess around. You don't want to leave it, thinking it will go away," he warns.

For problematic symptoms a visit to your doctor is essential. To help combat the stress, try practicing yoga, drinking black tea, getting more exercise and sleep, or increasing your intake of omega-3 fatty acids. For major stressors, though, a lifestyle change is likely required, says Atkinson.

"If stress is affecting your home life and work life over some reasonable amount of time and you're disabled by it, you want to get help," he says.