The Gut-Brain Connection & Alzheimer's Disease

The brain-gut connection has become a topic of growing interest over the years. It is well known that gut health is truly the foundation of overall health. Of course the digestive system plays a role in energy production, by allowing us to break down the foods we eat to absorb nutrients. It also plays a role in detoxification, by eliminating toxins and waste products from the body via the feces. The digestive system is also the first line of contact between our bodies and the outside environment, and home to millions of bacteria - making it the forefront of our immune system. In addition, the digestive system produces many of our hormones (such as serotonin and dopamine), which influence our mood, sleep and the nervous system. When the integrity of the digestive system is compromised, it leads to whole-body symptoms such as fatigue, anxiety, depression, hormonal imbalances, skin issues, inflammatory and autoimmune conditions. Emerging research has identified a genetic overlap between Alzheimer's disease and disorders of the gastrointestinal tract:

• Gastroesophageal Reflux Disease (GERD)

• Peptic-Ulcer Disease (PUD)

• Irritable Bowel Syndrome (IBS)

• Diverticulosis

• Gastritis

• Dysbiosis

In addition to the shared genetics, researchers found other important metabolic links between gut disorders and the development of Alzheimer's disease, the most common type of dementia. Cholesterol was found to play a key role, in that abnormal levels of cholesterol have been shown to be a risk factor for both Alzheimer's disease, and gut disorders. High levels of cholesterol has the ability to increase permeability of the blood-brain-barrier, resulting in abnormal cholesterol metabolism, cellular dysfunction, inflammation, plaque formation, and defects in cellular signalling neuronal cell death Alzheimer's disease. The current literature also suggests that abnormal blood lipids are worsened by imbalances in the gut microbiota (also referred to as dysbiosis), and gut infections (such as H.pylori). This cascade of abnormal lipid metabolism is thought to be a potential biomarker for Alzheimer’s disease and GI disorders. Adherence to a Mediterranean diet is thought to be an effective preventive, and non-pharmacologic approach for the management of hypercholesterolemia, and abnormal lipid profiles. The Mediterranean diet involves the following:

• Daily practices of physical activity and family time

• Daily consumption of vegetables, fruits, healthy fats, whole grains, and legumes

• Fish, seafood and omega-3 rich foods >3 servings/ week

• No more than 1-2 servings/ week of poultry, eggs and dairy

• Red meats and sugar to be consumed sparingly, and in small amounts.