Browse evidence-based analysis of health-related claims and assertions
When people do supervised weight training for 20 weeks, their muscles make more of a protein called VDR—and that’s linked to gaining more muscle mass, but not to getting stronger or having more vitamin D in their blood. So VDR might be a sign that muscle growth is happening, even if vitamin D levels don’t change.
Correlational
When scientists turned up the vitamin D receptor in the leg muscles of rats for 10 days, the muscle fibers got bigger, the muscles made more protein, and key growth signals kicked in—so it looks like boosting this receptor might help muscles grow.
Mechanistic
Scientists know a lot about how insulin works in people with type 2 diabetes, but they still don’t have much direct information on how leptin behaves in the bodies of lean or obese people—even after many years of studying it.
Descriptive
Even when the brain stops listening to leptin to stop eating, it still listens to leptin to keep the reproductive system working — so obese people don’t become infertile just because they’re overweight.
In mice that get fat from eating junk food, too much leptin actually makes their brain stop responding to it — but if you lower leptin levels, their metabolism improves.
When your body has enough energy, it sends a hormone called leptin to your brain to say 'we're good.' But when you're starving and leptin drops, your brain slows down things like reproduction and metabolism to save energy—and if you give leptin back, those functions start working again.
When people get obese, their bodies make a lot of a hormone called leptin that’s supposed to tell the brain to eat less, but the brain stops listening — so they keep gaining weight.
In healthy young people, those with higher levels of a waste product called creatinine in their blood tend to have less of a nighttime drop in blood pressure—no matter how much salt they eat or if they take ketone supplements.
Eating a lot of salt for a short time or taking ketone supplements won’t change how much your blood pressure drops at night if you’re a healthy young adult.
If healthy young adults eat a lot of salt and take ketone supplements for 10 days, their kidneys don’t show any signs of stress or damage based on common blood and urine tests.
Causal
In China, when people were encouraged to eat less salt over three years, their urine showed a big drop in salt relative to potassium—and the people who started with high blood pressure saw the biggest changes. This suggests cutting salt might help those at highest risk for heart problems the most.
In China, people who used a special spoon that measures exactly 2 grams of salt ended up eating less salt than those who switched to low-salt seasoning—suggesting that changing how you cook might work better than just swapping out your salt.
In China, people who cook with a lot of salt and actually use a special spoon to measure less salt ended up excreting much less salt in their urine than people who didn’t use the spoon — showing that using the tool correctly makes it work better.
People in China who lowered the balance of salt to potassium in their urine the most over three years ended up with much smaller increases in their blood pressure — some didn’t even see their bottom number (diastolic) go up at all, and their top number (systolic) only rose a little.
People in China who used a special spoon that measures exactly 2 grams of salt while cooking for three years ended up excreting less salt in their urine than those who didn’t use it—meaning the spoon helped them eat less salt.
When people with type 2 diabetes eat less salt, their blood pressure tends to go down in a similar way across different studies — it’s not all over the place.
If people with type 2 diabetes eat less salt, their bodies pee out about 38 millimoles less sodium in a day, which means they’re actually following the low-salt diet.
Quantitative
Cutting back on salt in your diet can lower your blood pressure a bit—about 5.6 points for the top number and 1.7 points for the bottom number—if you have type 2 diabetes.
Tumors with giant cells almost never show up in the skull — they’re much more common elsewhere in the body.
Eating more whole foods like fruits, veggies, and nuts—while cutting back on salty, sugary, and processed stuff—might be a better and easier way to improve your health than just trying to eat less salt.
Eating too little salt—like only 5 grams a day—might actually be bad for you, even though we usually think salt is bad. Your body needs some sodium to work right, and going below what most people eat globally could be risky in ways we don’t fully understand yet.
Eating more potassium-rich foods like bananas, spinach, and potatoes is linked to a lower risk of heart problems.
Too little or too much salt might both be bad for your heart — studies show people who eat way too little or way too much salt may be more likely to die from heart problems.
Eating too much salt might raise your blood pressure, but we’re not sure if cutting back on salt actually helps prevent heart problems because no big, fair studies have proven it yet.