High potassium foods can protect against a number of diseases. Hypertension is the disease most strongly shown to be prevented by high potassium foods. By getting a proper ratio of potassium to sodium in your food you provide an electrochemical balance within your cells. This balance provides cell restoration quickly so the cell can function optimally. For your cells to function best, potassium and sodium must pass through multiple channels in the membranes of the cell. If these channels do not allow potassium and sodium to pass properly, cell restoration occurs slowly and disease will result. The last post discussed how the malfunction of some genes that produce the proteins of these channels is associated with hypertension. Another way the channels can function poorly depends on the lipids (fats) that the membranes are composed of.
Excessive saturated fat makes the membranes too stiff, so the channels do not open and close as well as they should. Polyunsaturated and monounsaturated fats make the membranes more fluid. They allow the channels to function better, and allow certain cell messages to be transmitted more easily within the cell. The cell does its work better and restores itself better.
One particular lipid of great interest is PIP2. More and more publications are showing how important it is. It is best known for its role in cell signaling, being split into two molecules that are secondary messengers within the cell. A recent publication (1) reviewed another important function of PIP2. Although PIP2 regulates multiple types of ion channels, the review limited its discussion. It only discussed how PIP2 controls a certain small group of potassium channels.
PIP2 binds strongly to a part of these potassium channels that controls their opening and closing. It causes the channel to open or close depending on the difference in electrical charge (voltage) between the inside and outside of the cell. This difference in charge depends on how much sodium and potassium are inside and outside the cell. And how much sodium and potassium are inside and outside depends on how much are in the food you eat.
These particular channels are the ones that are involved in cell restoration. They help the cell restore itself to a resting state after the cell has performed its function. For example, these channels allow a nerve cell that has discharged and sent a message somewhere in your body to restore itself. This allows the cell to send another message all over again – many times a second. If the channel opens and closes too slowly, the nerve cell will not restore itself fully and the nerve will not function as well as it could.
Of course, this is true for every cell in the body. All cells use similar channels. The specific cells already shown to be affected by this small subset of channels are heart rhythm cells, nerve cells and cells of the inner ear. So considering all the channels that PIP2 regulates, all cells (heart, lung, liver, kidney, immune, etc.) in the body will not function as well as they could if potassium and sodium were in balance.
This may be a part of the reason polyunsaturated and monounsaturated fat are better for heart and blood vessel health than saturated fat. They increase the fluidity of the cells' membranes. This allows PIP2 to open and close channels better. Quick restoration of the cell to its resting state means the cell is quickly ready to get back to work again. The cell can perform more work in a given amount of time.
Potassium Sodium Food Tables
How can you be sure your cells are functioning optimally? Get the right ratio of potassium and sodium in your diet. Links to tables with the potassium and sodium content of many foods can be found here.
There is little reason to be concerned about getting enough PIP2. It is made in our bodies from its precursor phosphotidylinositol. Phosphotidylinositol is found widely in a variety of foods. It is a component of lecithin and phytate. Phytate is a less absorbable form than lecithin. However, if you are getting a variety of high potassium foods, you are getting plenty of PIP2 precursor.
1. PIP2 regulation of KCNQ channels: biophysical and molecular mechanisms for lipid modulation of voltage-dependent gating. Zaydman MA, Cui J. Front Physiol. 2014 May 27;5:195. doi: 10.3389/fphys.2014.00195. eCollection 2014.