Women who regularly drink coffee throughout the day may want to reconsider another cup, according to research linking very high consumption with lower bone mineral density. However, the findings suggest moderate coffee intake was not associated with negative effects on bone health.

Researchers at Flinders University published the study in the journal Nutrients. They examined coffee and tea consumption among 9,704 women age 65 and older over a period of 10 years.

During that time, researchers measured bone mineral density at the hip and femoral neck. These are areas where fractures related to osteoporosis commonly occur.

Drinking tea was associated with higher total hip bone mineral density, according to the results. Meanwhile, consuming more than five cups of coffee per day was associated with lower bone mineral density.

Here's What They're Not Telling You About Your Retirement

The findings did not show the same negative association for moderate coffee consumption. Drinking about two to three cups per day was not associated with harmful effects on bone health.

Researchers also identified differences connected to participants’ health and lifestyle factors. Coffee consumption was associated with lower femoral neck bone mineral density among women with higher alcohol intake.

At the same time, the positive association between drinking tea and bone density was more pronounced among women with obesity. The findings reflected associations rather than proof that either beverage directly caused changes in bone density.

The researchers described osteoporosis, which is characterized by low bone mineral density, as "a major global public health concern affecting individuals across all ages, genders and ethnicities."

This Could Be the Most Important Video Gun Owners Watch All Year

About one in three women and one in five men age 50 and older worldwide experience fractures related to osteoporosis, according to the study. Women face particularly high risk because they generally have lower bone mass and experience accelerated bone loss after menopause.

In the U.S., the number of adults age 50 and older with low bone mineral density in the hip or spine is projected to increase by 17.2 million by 2030. Researchers noted the health care costs and long term disability associated with fractures related to osteoporosis.

The scientists examined coffee and tea because dietary factors play a "crucial role in the prevention of noncommunicable disease and may influence bone health." Coffee and tea are also two of the most widely consumed beverages worldwide.

Study coauthor Ryan Liu told ScienceDaily that "compounds called catechins, abundant in tea, may promote bone formation and slow bone breakdown."

"Coffee’s caffeine content, by contrast, has been shown in laboratory studies to interfere with calcium absorption and bone metabolism, though these effects are small and can be offset by adding milk," Liu said.

"Our results don't mean you need to give up coffee or start drinking tea by the gallon," Liu added. "But they do suggest that moderate tea consumption could be one simple way to support bone health and that very high coffee intake might not be ideal, especially for women who drink alcohol."

Lisa Young, a registered dietitian and adjunct professor of nutrition at New York University, urged caution when interpreting the research. "Because it followed women over time without assigning them to drink coffee or tea, it can only show associations, not prove that coffee weakens bones or that tea strengthens them."

Young noted several limitations, including differences in participants’ lifestyles and the study’s focus on bone density rather than fractures. She also said the effects were relatively small and appeared mainly among older women.

Symptoms of osteoporosis and early bone loss include back pain, loss of height over time and stooped posture, according to the Mayo Clinic. Young said the overall message for coffee drinkers remains reassuring.

"The bottom line for the public is reassuring: Moderate coffee intake appears fine, and there is no need to switch drinks for the sake of your bones," Young said.

"The most proven ways to protect bone health remain getting enough calcium and vitamin D, staying physically active and avoiding smoking and excess alcohol," she added. Young also made a case for moderate amounts of coffee, while cautioning that too much of anything is never good.