Are you walking into rooms but can't remember why? Staring into the refrigerator and wondering what you needed? Forgetting familiar phone numbers? Maybe an orange or a carrot would help.

A study from the University of Ulm suggests that people with mild dementia – an early sign of Alzheimer's Disease – have significantly lower blood concentrations of vitamin C and beta-carotene than their healthy counterparts.

The researchers suggest it might be possible to influence the development of Alzheimer's Disease by your diet or by taking dietary antioxidants.

Alzheimer's Disease is the leading cause of dementia and the 6th leading cause of death in the U.S.  It affects about 5.3 million Americans and 12 million people worldwide. Every 69 seconds another person is diagnosed with Alzheimer's Disease.

A neurodegenerative disease, Alzheimer's is believed to be caused by the accumulation of amyloid-beta plaques and a loss of synapses between neurons in the brain. Oxidative stress, the process that produces free radicals in cells, is believed to promote its development.

In this study, researchers wanted to know if antioxidants – compounds that combat free radicals – could protect against the brain degeneration.

They looked at whether low blood-serum levels of certain antioxidants – vitamin C, vitamin E, beta carotene, lycopene and coenzyme Q10 – could be a risk factor in the onset and development of Alzheimer's Disease. They studied 74 patients with mild dementia and 158 healthy controls, all aged between 65 and 90 years.

Published in the Journal of Alzheimer's Disease, their results show that the concentration of vitamin C and beta-carotene in the serum of Alzheimer's patients was significantly lower than in the blood of control subjects.

However, no difference was found between the groups for the other antioxidants tested - vitamin E, lycopene and coenzyme Q10.

The researchers believe that their results need to be confirmed in a larger prospective study to determine whether in fact vitamin C and beta-carotene might prevent the onset and development of Alzheimer's disease.

Bottom line? Keep your mind sharp by eating lots of fruits and vegetables, especially those high in vitamin C and beta-carotene.

Vitamin C is an antioxidant found in high concentrations in citrus fruits such as oranges, lemons and grapefruit, as well as in many other fruits and vegetables like bell peppers, kale, kiwi and strawberries.

Beta-carotene is a precursor to vitamin A and is responsible for the pigment in orange colored fruits and vegetables.  It's also found in red, yellow, and green colored fruits and vegetables. Most people get their beta-carotene through eating carrots but other rich sources include cantaloupe, broccoli, apricots and spinach.