NEW YORK, Oct 29: You may have encountered various claims about the benefits of citrus fruits—such as using them to lighten hair inexpensively, sniffing lemon juice to avoid motion sickness, or drinking a morning mix of lemon juice and olive oil for health benefits. Recently, a TikTok user named Jess Lynne popularized the "lime sleep hack," which involves slicing a lime in half, placing it in a bowl, and setting it next to a child's bed to promote uninterrupted sleep.

While citrus fruits like lemon, lime, orange, and grapefruit have numerous health benefits, not all claims are substantiated. Here’s a look at what citrus can and cannot do.

Can limes aid in sleep?

Lynne, a psychic medium, told Yahoo Life via email that her inspiration came from various cultures that have used limes throughout history “to rid negative, fear-based energies and dark entities in their surroundings” and to “promote peaceful sleep.” However, Dr. Luis Ortiz, a sleep medicine physician at Johns Hopkins All Children’s Hospital, states that there is limited clinical evidence to support the idea that lime scents improve sleep; most of this research is preliminary and has not been rigorously studied.

Ortiz acknowledges that the aroma of citrus might help individuals relax before bedtime, and while some studies suggest that aromatherapy can alleviate anxiety, others indicate that citrus essential oils may actually increase alertness and reduce drowsiness. This effect, he points out, would not be conducive to sleep.

Although smelling cut limes is unlikely to harm anyone, Ortiz advises caution with essential oils, including lime-based ones. “You never want to ingest them, and you shouldn’t use a water-based diffuser, as it can linger in the room for extended periods,” he says. “Overexposure to essential oils can irritate the lungs and interfere with mucus clearance.”

Can smelling lemon prevent motion sickness?

Possibly, according to registered dietitian Krutika Nanavati. The citric acid in lemons may have a “calming effect” on the stomach and distract from feelings of nausea. However, she notes that these benefits are not exclusive to citrus; peppermint and ginger can also help relieve nausea and motion sickness.

Can citrus prevent cancer?

In general, yes. Heidi Silver, a research professor at Vanderbilt University Medical Center, explains that data shows consuming citrus fruits reduces the risk of certain cancers, particularly oral cancers, pharyngeal, esophageal, lung, kidney, and bladder cancers. However, there is evidence linking citrus consumption—particularly oranges and orange juice—to an increased risk of melanoma. Silver explains that this is due to interactions between components in citrus juice and ultraviolet rays.

Moreover, individuals who consume excessive citrus juice and have significant sun exposure may be at a higher risk for three types of skin cancers: basal cell, squamous cell, and melanoma.

Can citrus aid in weight loss?

Silver believes it’s possible. She co-authored a study indicating that individuals who consumed half a grapefruit or half a cup of grapefruit juice before each meal lost more weight than those who drank water before meals on a reduced-calorie diet. Participants consuming grapefruit also experienced increased “good cholesterol” (HDL), reduced appetite, and higher vitamin C levels, which are often under-consumed in the U.S.

Can citrus help prevent kidney stones?

Yes, particularly lemons and limes. Silver states that increased citrus intake can elevate citrate levels in urine, which binds to excess calcium, a common cause of kidney stones. “So, consuming citrus can help prevent kidney stones or their recurrence,” she says. How about some lemon water?

Can citrus prevent cardiovascular disease?

Perhaps. A 2011 study in Japan found that frequent consumption of citrus fruits could lower the risk of cardiovascular diseases, including stroke and cerebral infarction. The flavonoids in citrus may help reduce inflammation, which increases heart disease risk. Dr. Michael Ayers, an assistant professor of cardiology at UVA Health, suggests that anything mitigating inflammation likely slows heart disease progression. However, he adds that “the body of evidence supporting individual food groups having a significant effect on cardiovascular outcomes is minimal at best and speculative at worst.”

Ayers believes there’s little harm in adding citrus to one’s diet to see if it helps. Still, the type of citrus consumed matters. “You should eat the whole fruit rather than just drinking the juice,” emphasizes Dr. Ana Baylin, an associate professor of nutritional sciences at the University of Michigan School of Public Health. “While juice contains vitamin C, it lacks fiber,” making it less beneficial.

Should anyone avoid citrus?

Given its high acidity, Baylin advises that individuals with gastritis or ulcers may want to limit citrus consumption. Excessive citric acid can also lead to dental erosion, according to Silver, so those with dental issues should be cautious when consuming citrus fruits.

Baylin also notes that grapefruit and grapefruit juice should be approached carefully, as they can interact with certain medications. Silver specifies that individuals taking statins or those with chronic conditions on immunosuppressant drugs should avoid citrus, particularly grapefruit.

While there are many good reasons for most people to enjoy citrus, overconsumption is possible. If you experience gastrointestinal symptoms like diarrhea or bloating after eating, say, your fourth orange of the day, you may be consuming too much, Silver advises.