My blood pressure reads at prehypertension, and my doctor suggested I lower my sodium intake. So, I am going to do this, but I am curious as to why and how sodium affects our blood pressure. Also, how much sodium should I be having (or not having, rather) each day to make a difference? I honestly have no idea how much I consume on average. Thanks! -Jebedie W.
Sodium affects your blood pressure through expanding blood volume and a complex mechanism involving cells, hormones, enzymes and organs (namely your kidneys) called the renin angiotensin aldosterone system. Aren’t you glad you asked? The layman’s explanation is that sodium increases solute concentration of the blood fluid requiring the influx of liquid to dilute it back to normal. The resulting force of the now expanded blood pushing against blood vessel walls (blood pressure) is higher than before.
The American Heart Association recommends limiting daily sodium intake to no more than 1,500 milligrams while the Institutes of Medicine recommend a limit of 2,300 milligrams daily. The average American consumes nearly 4,000 milligrams daily — nearly double the recommended limits. Easy to do even with “healthy” packaged foods, salad dressings, frozen foods and convenience items. Now consider this: the amount your body actually requires is only 500 milligrams! Track your intake for a week using quality nutrition analysis software to see where your current intake falls, then start cutting back accordingly.
Reducing sodium in the diet (along with exercise and weight loss if needed) is a great first line approach to treating hypertension. The best benefits are seen when potassium is increased as well since this mineral opposes the fluid-related action of sodium. Potassium is found in fresh fruits, vegetables, lean meats, fish and low-fat milk products. Potatoes, bananas, beans, winter squash and dark green leafy vegetables are highest in potassium. Yogurt, salmon, avocado and mushroom are good sources.
It is important to note that only a small percentage of the population is sodium sensitive. Following a restricted diet and measuring your blood pressure regularly are the only way to know if you’ll respond to the intervention. Because blood pressure changes by the minute and there are so many factors that affect it, following a prescribed course of action over time will likely determine effectiveness. – Debbie J., MS, RD
This article should not replace any exercise program or restrictions, any dietary supplements or restrictions, or any other medical recommendations from your primary care physician. Before starting any exercise program or diet, make sure it is approved by your primary care physician.
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