How Reducing Salt Intake Can Improve Microbiome Health

A recent study found that when people reduced the amount of sodium they consumed, their gut bacteria produced higher levels of beneficial compounds that reduce inflammation and improve metabolic health. Some experts suspect that a high-sodium diet contributes to hypertension by disrupting the gut microbes that help regulate your blood pressure.

“We know from studies that even slight changes in the amount of salt you eat can impact microbes in the colon,” said Chris Damman, a gastroenterologist at the Digestive Health Center at University Medical Center. of Washington and author of Gut Bites. MD, a gut health blog. Salt appears to affect the health and growth of these microbes, “as well as the extent to which they are able to produce the healthy factors that help regulate our appetite and metabolism,” Damman said.

Most adults consume way too much sodium without even realizing it. Most of the sodium we consume doesn’t come from the table salt we add to our foods. About 70 percent of dietary salt comes from ultra-processed and packaged foods like bread, pizza, chips, deli meats, canned soups and hamburgers. Health officials recommend that adults consume no more than 2,300 milligrams of sodium per day – the amount contained in about one teaspoon of table salt – while the average American consumes about 3,400 milligrams of sodium per day.

Eating that much sodium can raise your blood pressure, increasing your risk of heart attacks and strokes. But scientists have also shown that excessive sodium consumption has a direct impact on your gut microbiome. Here are some of the effects of excess salt:

• Fewer healthy microbes: In small clinical trials, they found that a diet high in salt led to a strong reduction in important gut microbes such as lactobacilli, which play a key role in the immune system and our inflammation levels. Several animal studies have also documented this.
• More harmful microbes: Scientists have found in large observational studies that people who consume higher levels of sodium are more likely to harbor disease-causing bacteria in their intestines.
• Less microbial diversity: These same studies show that salt eaters tend to have less microbiological diversity, which is linked to higher rates of obesity, hypertension and other chronic diseases.
• Fewer short-chain fatty acids: Short-chain fatty acids are produced by our gut microbes and research shows they are good for our metabolic health. A striking randomized study asked 145 adults with untreated hypertension to follow a low-sodium diet or a normal diet for six weeks. Researchers found that when participants ate less sodium, they had higher levels of short-chain fatty acids, lower blood pressure, and improved blood vessel health compared to a diet higher in sodium. . The findings suggest that when given the right diet, our gut microbes produce compounds that can help lower blood pressure, said Haidong Zhu, lead author of the study and professor in the departments of Medicine and Family Medicine and community at the University of Washington. Augusta University in Georgia.

How to remove salt from your diet

Keep an eye out for processed foods. Ultra-processed foods almost always contain more sodium than minimally processed foods like fresh fruits, vegetables, meat, poultry, eggs, fish, milk and plain yogurt. Replacing ultra-processed foods with fresh foods means you’ll invariably end up consuming less sodium.

Read the labels: If you eat packaged foods, make a habit of checking their sodium content. In general, a food is considered weak in sodium if it provides 5 percent or less of the daily value of sodium per serving. Conversely, a food is considered high in sodium if it contains 20 percent or more of the daily value of sodium per serving.

Watch out for salt bombs. According to the federal government, most adults get about 40 percent of their sodium from nine categories of foods. These include pizza, soups, deli sandwiches, savory snacks (chips, crackers, popcorn), burgers, burritos and tacos, poultry, pasta dishes, eggs and omelets. Be careful of these foods and be aware that they could add excessive amounts of sodium to your diet.

Use salt substitutes: Salt isn’t inherently bad, said Damman of the University of Washington. We need salt in our diet. It’s just that we eat way too much of it. One way to reduce the effects of salt on your health is to increase your potassium intake. A large meta-analysis published in April in Annals of Internal Medicine found that people who replaced table salt with salt substitutes containing potassium chloride and sodium chloride (instead of sodium chloride alone) were significantly less likely to die prematurely from heart or other disease. causes compared to people who used regular salt. Other studies have also shown that replacing regular salt with potassium-containing salt substitutes lowers blood pressure.

Eat more foods rich in potassium: Focus on adding the following potassium-rich foods to your diet: leafy greens, root potatoes, beans, lentils, chickpeas, butternut squash, and fruits like avocados, bananas, oranges, mangoes , kiwis, prunes, raisins, dates and dried apricots.

Use the seasoning. Instead of flavoring your food with table salt, try using garlic powder, black pepper, sesame seeds, and other herbs, spices, and seasonings instead.

Do you have a question about healthy eating? E-mail EatingLab@washpost.com and we may answer your question in a future column.