Do carbohydrates and added sugars raise or lower blood pressure in adults?

Carbohydrates and Added Sugars Raise Blood Pressure

Added sugars, particularly from sugar-sweetened beverages, consistently raise blood pressure and increase hypertension risk, while refined carbohydrates (white bread, white rice, crackers) produce similar harmful effects through rapid glucose spikes. 1, 2, 3

The Evidence on Added Sugars and Blood Pressure

Sugar-sweetened beverages are the most problematic, with compelling evidence showing:

• Each 250g/day increment of sugar-sweetened beverages increases hypertension risk by 26% and raises systolic blood pressure by 0.24 mmHg 2
• Consuming just one soft drink per day significantly increases odds of developing hypertension, as documented in the Framingham Heart Study 1
• A systematic review of 12 studies (409,707 participants) found that 10 of 12 studies showed statistically significant positive associations between increased sugar-sweetened beverage intake and hypertension 3

The mechanisms are multifactorial: fructose increases hepatic triglyceride synthesis, de novo lipogenesis, and VLDL secretion, contributing to vascular dysfunction 1, 4. High-dose fructose also increases uric acid production and promotes visceral adiposity 5.

Refined Carbohydrates Have Similar Effects

Refined grains and high-starch vegetables produce blood glucose and insulin responses similar to simple sugars, making them equally harmful 5:

• White bread, white rice, crackers, cereals, and russet/white potatoes are rapidly digested, causing brisk rises in blood glucose and insulin 5
• These foods stimulate hepatic de novo lipogenesis, increase uric acid production, and promote visceral adiposity 5
• The American Heart Association explicitly recommends restricting both refined grains and added sugars for cardiometabolic health 5, 6

Important Nuances on Carbohydrate Quality

Not all carbohydrates raise blood pressure—the type matters critically:

• Protective carbohydrates: Fruits, legumes, vegetables, and minimally processed whole grains actually lower hypertension risk and 24-hour blood pressure 7
• The chemistry-based classification of "simple" versus "complex" carbohydrates is physiologically irrelevant; what matters is fiber content, glycemic response, processing level, and whole grain content 5
• When whole grains remain intact (quinoa, steel-cut oats), the bran protects the starchy endosperm from rapid digestion, reducing glycemic responses 5

The Sugar-Salt Synergy

A critical pitfall: Sugar and salt consumed together produce synergistic blood pressure elevation 8:

• Sugar intake enhances salt sensitivity through urinary sodium retention and insulin resistance 8
• The greatest blood pressure increases following sugar challenges occur in individuals with the highest sodium excretion 8
• In laboratory studies, combining sugar and salt challenges caused synergistic blood pressure elevation, while sugar alone did not increase blood pressure during marked sodium depletion 8

Specific Recommendations

Limit added sugars to no more than 100 calories/day for women and 150 calories/day for men (approximately 6 teaspoons or 25g for a 2000-calorie diet) 1, 6:

• One 12-oz soda contains about 10 teaspoons of sugar—already double the recommended daily limit 6
• Avoid sugar-sweetened beverages entirely, as they show the strongest association with hypertension 1

Restrict refined grains and high-starch vegetables 5, 6:

• Currently, nearly 3 in 4 Americans consume too many refined grain products 5
• Replace white bread, white rice, crackers, and bakery desserts with minimally processed whole grains 6
• Limit white or russet potatoes, which have metabolic characteristics similar to refined grains 5, 6

Focus on high-quality carbohydrates 6:

• Vegetables, fruits, legumes, and minimally processed whole grains should form the foundation of carbohydrate intake 6
• Target at least 25g of fiber daily from whole food sources 5, 6
• These foods contain fiber, vitamins, minerals, and phytochemicals that actively protect against disease 6

Clinical Context

The evidence is particularly strong for sugar-sweetened beverages, where dose-response relationships have been consistently demonstrated 2, 3. The European Society of Cardiology specifically states that sugar-sweetened beverages "should be strongly discouraged as they can increase blood pressure and lead to cardiovascular complications" 1.

For refined carbohydrates, the 2015 Dietary Guidelines Advisory Committee explicitly advises restriction of both refined grains and added sugars, recognizing that many consumers erroneously believe refined grain products are beneficial when promoted as "low-fat" or "fat-free" 5.