Eggs Can Reduce High Blood Pressure
I’ve always thought of eggs as a super food. It is one of those foods that nutrition gurus across the world say we should eat. In the past, due to their high cholesterol content, experts advised that eggs were best eaten sparingly. Interestingly enough, many claim that there is no correlation between eggs and heart disease, the number one cause of death in North America. Researchers now are saying that the egg can also help reduce high blood pressure. Another benefit from our famed superhero, the egg. The study was reported in the Journal of Agricultural Food Chemistry.
Eggs consist of 75% water, 12% proteins, 12% lipids (fats), and 1% vitamins, minerals, and carbohydrates. Rich in bioactive proteins and peptides (short polymers formed from the linking of amino acids), eggs are a vehicle used to lower high blood pressure. Scientists at the University of Alberta, Edmonton have found that the process of cooking eggs leads to more of these helpful proteins and peptides.
During digestion, the peptides are either absorbed through the intestine or locally through the gastrointestinal tract. Antimicrobrial, anticancer, antihypertensive peptides and protease inhibitors all have been reported present in eggs. One particular enzyme known as ACE (Angiotensin converting enzyme) was of particular interest to the researchers at the univeristy.
ACE is an enzyme responsible for regulating blood pressure. It is part of the rennin-angiotensin system which which helps maintain stable cardiovascular functions. ACE catalyzes the formation of angiotensin II (from angioetensin I), a potent vaso constrictor chemical which causes muscles to narrow blood vessels. This results in the increasing of vascular resistance, decreasing blood flow, and ultimately to high blood pressure. The compounds in the egg work to inhibit the formation of ACE.
Pharmaceutical companies have also guided efforts for antihypertensive drug development. These drugs, aptly named ACE inhibitors, slow the activity of ACE. Captopril, Benazepril, and Enapril are a few that belong to this category. Often prescribed by doctors, these drugs are based on the same essential concept which is to inhibit ACE. Side effects do occur for certain people and it is best to let a physician handle those issues.
Considering that table consumption accounts for 70% of total egg consumption in North America, differing cooking methods were addressed by the researchers. The eggs were cooked two ways:
• Boiling for 10 minutes, cooling for 5 under cold water, and then peeling.
• Frying after separating whites and yolk (each fried separately).
After cooking, they were frozen immediately and then subjected to varying scientific and metabolic processes such as changing pH and introducing pancreatic digestive enzymes. This was done to mimic the metabolic actions in the gut.
The results showed that the fried egg had the strongest inhibitory factor. Researchers hypothesized that this may be due to the fried egg having been cooked at a higher internal temperature (170 °C ) than the boiled egg (100 °C), which may have affected the release of bioactive peptides.
Be it fried eggs, egg salad, egg drop soup, or eggs Benedict, it seems that our superhero still belongs to the super food hall of fame.
Reference
J. Agric. Food Chem., 2009, 57 (2), pp 471–477