One out of every three US adults has high blood pressure (hypertension).If you’re among them, one of the first recommendations your physician probably gave you was to cut back on salt.
Yet, there’s far more to maintaining a healthy blood pressure than eating a low-salt diet – a strategy that works for some people and fails for others.
In fact, fewer than half of Americans with high blood pressure have their condition under control, and perhaps this is because conventional physicians have been focused on the “wrong white crystals,” namely salt instead of sugar.
One of the primary underlying causes of high blood pressure is related to your body producing too much insulin and leptin in response to a high-carbohydrate (i.e. high sugar) and processed food diet.
Why the DASH diet can lower blood pressure
You’ve probably heard of the DASH diet, which is claimed to be among the most effective for controlling hypertension. It consists largely of fresh vegetables, fruits, lean protein, whole grains, low-fat dairy, and very low sodium content.
But it’s ALSO low in sugar/fructose. So, while people on DASH diets do tend to show reduced hypertension, the reason for this may not be solely the reduction in salt, but the reduction in sugar.
The same holds true for reducing your intake of processed foods, which are top sources of both heavily processed salt and sugar/fructose. In a new review in the journal Open Heart, the authors also argue that the high consumption of added sugars in the US diet may be more strongly and directly associated with high blood pressure than the consumption of sodium.
Research also shows that drinking a single 24-ounce fructose-sweetened beverage leads to greater increases in blood pressure over 24 hours than drinking a sucrose-sweetened beverage, which again points to the detrimental effects of fructose on your health. The Open Heart study authors concluded:
“It is time for guideline committees to shift focus away from salt and focus greater attention to the likely more-consequential food additive: sugar. A reduction in the intake of added sugars, particularly fructose, and specifically in the quantities and context of industrially-manufactured consumables, would help not only curb hypertension rates, but might also help address broader problems related to cardiometabolic disease.”
How Excess Sugar Causes High Blood Pressure
In order to effectively treat and recover from high blood pressure, it’s important to understand its underlying cause, which is often related to your body producing too much insulin and leptin in response to a high-carbohydrate and processed food diet. As your insulin and leptin levels rise, it causes your blood pressure to increase. Eventually, you may become insulin and/or leptin resistant.
As explained by Dr. Rosedale, insulin stores magnesium, but if your insulin receptors are blunted and your cells grow resistant to insulin, you can’t store magnesium so it passes out of your body through urination. Magnesium stored in your cells relaxes muscles. If your magnesium level is too low, your blood vessels will be unable to fully relax, and this constriction raises your blood pressure.
Fructose also elevates uric acid, which drives up your blood pressure by inhibiting the nitric oxide in your blood vessels. (Uric acid is a byproduct of fructose metabolism. In fact, fructose typically generates uric acid within minutes of ingestion.)
Nitric oxide helps your vessels maintain their elasticity, so nitric oxide suppression leads to increases in blood pressure. So any program adapted to address high blood pressure needs to help normalize both your insulin/leptin sensitivity and uric acid level.
As it turns out, by eliminating excess sugar/fructose from your diet, you can address all three issues (insulin, leptin, and uric acid) in one fell swoop.
As a standard recommendation, I recommend keeping your total fructose consumption below 25 grams per day. If you’re insulin resistant (the majority of Americans are), have high blood pressure, diabetes, heart disease, or other chronic disease, you’d be wise to limit your fructose to 15 grams or less per day, until your condition has normalized.
Sugar: Hiding in plain sight – Robert Lustig
SugarScience.org is a website that uses graphics, videos and science to show you the many links between excess sugar and chronic disease. It’s a product of Dr. Robert Lustig and colleagues, who have reviewed more than 8,000 independent studies on sugar and its role in heart disease, type 2 diabetes, liver disease and more.
The site points out that added sugar can be found in 74 percent of packaged foods, using at least 61 different names on food labels. If you see sucrose, sugar or high-fructose corn syrup, you’ll probably recognize that the food contains added sugars, but barley malt, dextrose, maltose and rice syrup (among many others) also signal added sugar.
The World Health Organization (WHO) recommends that no more than 10 percent of your daily calories (and ideally less than 5 percent) come from added sugar or natural sugar. At 5 percent, if you eat a 2,000-calorie daily diet, this amounts to 25 grams of sugar a day. For comparison, the average American eats closer to 82 grams of sugar daily.
Does Salt Play a Role in Hypertension?
While the role of sugar in high blood pressure is becoming clearer, what does this mean for advice to cut salt from your diet to boost heart health? Overindulgence in the typically used commercially processed table salt can lead to fluid retention, high blood pressure, swelling of your limbs, and shortness of breath. In the long term, it is thought to contribute to high blood pressure, kidney and heart disease, heart attacks, and heart failure.
However, compelling evidence suggests that while processed salt can indeed cause fluid retention and related health problems, numerous studies have, overall, refuted the salt-heart disease connection.
For example, a 2011 meta-analysis of seven studies involving more than 6,000 people found NO strong evidence that cutting salt intake reduces the risk for heart attacks, strokes or death. In fact, salt restriction actually increased the risk of death in those with heart failure. Some studies have shown a modest benefit to salt restriction among some people with high blood pressure, but the evidence does not extend to the rest of the population.
So what’s really going on? For starters, there’s a huge difference between natural salt and the processed salt added to processed foods and salt shakers in most homes and restaurants. The former is essential for good health, whereas the latter is best avoided altogether.
Another factor that can have a significant impact on whether salt will harm or help your health is the ratio between the salt and potassium in your diet. Among other things, your body needs potassium to maintain proper pH levels in your body fluids, and it also plays an integral role in regulating your blood pressure.
It’s possible that potassium deficiency may be more responsible for hypertension than excess sodium. Imbalance in your sodium-potassium ratio can lead to hypertension, and the easiest way to achieve this imbalance is by consuming a diet of processed foods, which are notoriously low in potassium while high in sodium.
Remember, processed foods are also loaded with fructose, which is clearly associated with increased hypertension risk, as well as virtually all chronic diseases.
This may also explain why high-sodium diets appear to affect some people but not others. According to a 2011 federal study into sodium and potassium intake, those at greatest risk of cardiovascular disease were those who got a combination of too much sodium along with too little potassium.
According to Dr. Elena Kuklina, one of the lead authors of the study, potassium may neutralize the heart-damaging effects of salt. Tellingly, those who ate a lot of salt and very little potassium were more than twice as likely to die from a heart attack as those who ate about equal amounts of both nutrients.
A key factor in high blood pressure is weight, and oestrogen dominance is linked to weight increase at menopause particularly for women on HRT. Oestrogen and the progestins in HRT adversely affect cell membranes resulting in sodium and water influx into cells (causing water retention) and loss of potassium and magnesium.
When supplemental progesterone is used the weight usually goes down as this excess water is excreted and the blood pressure returns to normal.