1. Nutrient Deficiencies - If you're eating the typical American "junk food" diet, expect not only memory problems, but a lot of other health problems. Your brain needs nutrients to work right, particularly B-vitamins. Correcting your B-vitamin deficiencies alone can greatly help your nervous system including your brain function. Deficiencies of amino acids (protein building blocks) can also play a significant role.
2. Low Blood Sugar - Hypoglycemia causes a lack of glucose in the blood and therefore in the brain. It can produce mental spaciness, lethargy, and memory difficulties. If you notice episodes of poor memory when it's been too long since you've eaten, this is a likely cause. Eliminating refined sugar, eating a good whole foods diet with adequate protein, avoiding caffeine, and not skipping meals can help.
3. Candidiasis - Overgrowth of the common yeast organism, Candida albicans, frequently causes short-term memory problems and mental spaciness. Those symptoms are basically the response of the body to the toxins produced by the yeast organisms. This is a very common reason for memory problems in the non-elderly and elderly alike.
4. Food Sensitivities - Reactions to common foods can produce a very wide variety of symptoms, including mental fogginess and memory difficulty. Reactions to common foods like milk, wheat and yeast cause many to "space out."
5. Hormonal Imbalances - I have often observed with our pre-menopausal and menopausal clients, memory problems accompanying mental spaciness. If the memory difficulty coincided with hormonal changes, this is a likely cause. I've also observed this problem when women are on hormone replacement therapy that isn't quite right for their body.
6. Stress - In younger people, various forms of emotional stress tax the memory. Most people are just too busy to really enjoy optimum life and health. The average person is rushing around to and from work, and a hundred other commitments that frankly overload the brain. I like to think of the brain like a switchboard that can only have so many calls and then it's full. When you try to force your brain to handle more than it can comfortably handle, you forget things. This is your body's way of saving you from yourself! Slow down, do less, breathe once in awhile, stop and smell the roses, and recognize that everything depends on God, not on you.