Health Claims

If you're a healthy young man and you eat protein, fat, or drink water before a stressful situation, your stress hormone (cortisol) doesn't go up much more than if you'd eaten sugar instead.

Causal

When healthy young men get stressed out, the more their stress hormone (cortisol) spikes, the more their blood sugar tends to go up too.

Correlational

If a baby is exposed to fluoride while still in the womb or as a young child, it might affect how their brain grows and works, possibly by messing with their thyroid hormones, which could lead to lower IQ, changes in brain shape, or hearing problems.

Mechanistic

Your thyroid gland might soak up more fluoride than other parts of your body, which could make it more likely to get harmed by it.

Mechanistic

Too much fluoride might mess up the thyroid’s ability to handle harmful chemicals in the body, which could hurt the cells that make thyroid hormones and make the gland work less well.

Mechanistic

Fluoride might stop your thyroid from absorbing enough iodine, which it needs to make hormones—this could make an iodine shortage worse and mess up your metabolism.

Mechanistic

People who drink water with a lot of fluoride for a long time may have lower levels of certain thyroid hormones and higher levels of a hormone that tells the thyroid to work harder—this could mean their thyroid isn’t working quite right.

Correlational

Eating meat, eggs, and dairy gave our ancestors the nutrients they needed to grow smarter brains over thousands of years — so these foods might still help our brains work well today.

Causal

Long before humans existed, our ancient ancestors were eating meat and other animal parts, and scientists know this because they found cuts on old animal bones and special chemical traces in the bones of those early humans.

Descriptive

Eating meat and other animal foods helped early human ancestors change from living in forests and eating mostly fruit to living on open grasslands, and this diet change made their brains bigger and their guts smaller.

Causal

If you eat protein, fat, or just drink water before a stressful situation, your body’s stress hormone (cortisol) reacts about the same no matter what you ate or drank.

Descriptive

When healthy young men get stressed, the more their stress hormone (cortisol) spikes, the more their blood sugar tends to go up too.

Correlational

If a young man drinks sugar water before a stressful situation, his body releases more of the stress hormone cortisol than if he drinks protein, fat, or just water.

Causal

When older adults get more thyroid hormone—either through a shot or a pill—their prolactin levels drop by about 8–12% in just a couple of days, and this drop is bigger in men, suggesting thyroid hormone naturally lowers prolactin no matter how you give it or whether you're male or female.

Mechanistic

When healthy older men take a single pill of a thyroid hormone called T3, their body makes more of a hormone that tells the testes to work harder — but another hormone called TSH doesn’t do this, which suggests T3 has a special role in controlling this process.

Mechanistic

When older adults without thyroid problems are given hormones that boost thyroid activity, their stress hormone (cortisol) drops by about 12–16% over a couple of days, which suggests that the thyroid and stress systems talk to each other.

Correlational

In older adults who are healthy, giving them thyroid hormones (either through a shot or a pill) can make a key growth-related protein called IGF-1 go up by 6–9% in just one day — and this might happen even if their growth hormone levels don’t change.

Mechanistic

Taking one pill of a thyroid hormone called T3 might cause older men to temporarily produce more testosterone and a related hormone, which could help explain why thyroid and sex hormones might be connected as men age.

Correlational

Some chemicals in plants might be linked to serious diseases like cancer or diabetes, but we don’t know for sure if they cause them—other factors could be involved.

Correlational

Using just one way to process food, like boiling or soaking, doesn’t remove bad stuff as well as using two or more methods together.

Descriptive

Giving kids with early puberty a certain medicine doesn't seem to change their blood sugar, cholesterol, thyroid levels, testosterone, or bone strength during treatment.

Correlational

Scientists have found that ways like soaking, fermenting, or heating plant foods can help remove natural substances that make it harder for our bodies to absorb nutrients.

Descriptive

Soaking and sprouting beans, then cooking them under high pressure, can completely remove some of the natural chemicals that block nutrient absorption.

Quantitative

Some natural compounds in plants like beans and grains can stop your body from absorbing important nutrients like iron, protein, and vitamins, because they stick to those nutrients or mess with your digestion.

Mechanistic