The Complete Guide to Caffeine and Osteoporosis

The Science Behind Caffeine and Osteoporosis

Three Caffeine Caveats | Top Foods with Caffeine  | Is Coffee Bad For Your Bones? | The 9 Health Benefits of Coffee  | Caffeine and Osteoporosis – The Final Verdict

Caffeine and Osteoporosis – Not Only Safe, But Protective For Your Bones And Plenty More.

Recently, I heard from a woman with osteopenia who wanted to know if she should give up her morning cup of coffee.

She wrote:

“Would you be able to share with me what might have turned up about coffee consumption during all of your research on osteoporosis? I’m so confused about whether a cup of coffee (or two, or three cups) is harmful or not. I’m osteopenic and have a lot of back pain due to a series of auto accidents. Coffee helps clear my head in the morning and also seems to reduce my pain.”

Happily, I was able to assure her that drinking several cups of coffee daily is not only just fine, but highly beneficial for most people. (To view my video response to that question go to Is Coffee Bad For Your Bones? section)

Fact is: coffee is GOOD for our bones  – and plenty more. Your morning brew may help prevent not just osteoporosis, but type 2 diabetes, breast cancer, and Alzheimer’s disease to name a few of the most salient diseases, plus tastes great, energizes your morning, boosts your metabolism, and improves focus and concentration. YEAH, java!

Back in 2007, I wrote a blog for WebMD on coffee, entitled Java, No Jive, It’s Good for You!, in which I summarized more than a dozen of the latest papers reporting coffee’s beneficial effects. Since then, many more studies have not only confirmed their findings, but added to the list of coffee benefits – which makes my day as I love good coffee.

We have a serious espresso machine in our home. I make my husband, Dr. Joe Pizzorno, a mocha and myself, a cappuccino with organic coffee beans, organic soy milk and (for Joe, a spoonful of organic dark chocolate) every morning. He avoided coffee until I was asked to give a webinar on coffee by Dr. Bob Hedaya, MD, clinical faculty in psychiatry at Georgetown University and a friend of ours for many years. Doing the research for this talk, I pulled 70 pages’ worth of abstracts (abstracts are just a one paragraph summary of a medical journal article, so we’re talking many studies here) on the beneficial effects of coffee. Joe became convinced when he listened in and has been enjoying his mocha every morning since. I continue to follow the research on coffee as caffeine and osteoporosis is a hot topic. It’s definitely good for you – with very few exceptions (discussed in full under Three Caffeine Caveats below):

1. Those of us who can’t tolerate caffeine (but you can still get most of coffee’s benefits from decaf).
2. Women who are trying to conceive or are pregnant should play it safe and avoid caffeine.
3. Individuals with an unhealthy lipid profile (high small, dense LDL cholesterol levels) should avoid unfiltered coffee (but you can safely consume filtered coffee).

Three Caffeine Caveats

           1. If you’re caffeine intolerant, it’s in your genes

If coffee gives you the jitters or if a single cup of coffee in the morning or a piece of dark chocolate (which also contains caffeine) keeps you up half the night, caffeine is not your friend, and you should avoid not just caffeinated coffee, but all beverages, foods and medications that contain caffeine. Chances are you already know this, but you may not realize how many beverages and medications contain caffeine. Check out the Foods with Caffeine below.

If you’re sensitive to caffeine, a cup of caffeinated brew – or a caffeinated soda, dark chocolate or a drug that contains caffeine — can do worse than give you insomnia, it can increase your risk of a heart attack. The reason why lies in caffeine-intolerant individuals’ genes, which include a gene variant that produces a slowed down version of the liver enzyme responsible for metabolizing caffeine, so it can be cleared out of the body via the kidneys. This enzyme is called cytochrome P450 1A2 (CYP1A2).

The gene that delivers the directions for making CYP1A2 comes in different versions (called alleles), one of which slows down and another that increases the rate at which the enzyme works, and thus the rate at which caffeine is cleared from the body. We inherit 2 alleles for each of our genes. Individuals who have inherited even one of the CYP1A2*1F allele variants metabolize caffeine more slowly. If both CYP1A2 alleles are *1F, these are the folks who get speedy and stay awake all night after an afternoon cup of coffee, a piece of dark chocolate, or even a long-steeped cup of tea. In contrast, individuals whose genetic inheritance includes the gene variant CYP1A2*1A allele metabolize caffeine more rapidly. When both alleles are *1A, these people can top off a night out with an espresso and a serving of dark chocolate mousse and fall asleep an hour later. 

We first confirmed this when researchers from the University of Toronto, Canada, investigated whether the genetic variation in the gene that produces CYP1A2 could explain the inconsistency in studies, some of which show increased risk of non-fatal heart attack with coffee consumption while others do not. The team determined the genotype and assessed the intake of caffeine from coffee between 1994 and 2004 in 4,018 subjects from Costa Rica: 2,014 who were patients who had had a first acute non-fatal heart attack and 2,014 controls.

Results indicated that 55% of patients and 54% of controls were carriers of the slow *1F allele. Carriers of this allele older than age 59 who consumed 2-3 cups of coffee per day had a 36% increased risk of heart attack, and those who drank 4 or more cups per day had a 64% increased risk.

However, among carriers of the rapid *1A genotype older than 59, coffee consumption resulted in a reduced risk for heart attack of 25% for those consuming 1 cup, 22% for those consuming 2-3 cups, and 1% for those drinking 4 or more cups daily.

Even more pronounced increases and decreases in risk were seen in individuals younger than 59 years of age. Among younger individuals with the slow *1F allele, consuming just 1 cup of coffee daily increased heart attack risk by 24%, 2-3 cups increased risk by 67%, and 4 or more cups increased risk 133%!

Correspondingly, individuals younger than 59 with the rapid *1A genotype lowered their risk of heart attack by 52% when drinking 1 cup of coffee daily; 2-3 cups a day lowered risk by 43%, and 4 or more cups daily resulted in a reduction in heart attack risk of 17%. ⁽¹⁾

        2. Women who are trying to conceive or are pregnant

If you’re pregnant or trying to become pregnant, play it safe and avoid caffeine — particularly during your first trimester. This includes not just the caffeine in regular coffee but that found in tea (steep your tea for no more than 2 minutes), chocolate (if you must have chocolate, choose milk chocolate rather than dark chocolate), sodas (you should be avoiding these anyway for many reasons; drink sparkling water flavored with a bit of fruit juice instead), and some over-the-counter medications (check any medication you take for caffeine, over-the-counter medications included).

Once again, the reason lies in our genes. Women who carry the Val/Val polymorphism of another liver detoxification enzyme called CYP450 1B1 are at increased risk for first-trimester miscarriage, and, particularly in smokers, caffeine consumption further increases this risk.

CYP450 1B1 is not a major player in the processing of caffeine in the liver, but instead plays a role in the metabolism of caffeine among pregnant women via its action in the uterus.  Smoking increases risk since it is known to induce production of CYP450 1B1.

The CYP1B1 Val/Val polymorphism is very common, so avoiding caffeine is a good idea for women who are trying to conceive or are pregnant.

And giving up caffeinated coffee while pregnant may be easy, even for those who ordinarily love it. An increased aversion to coffee is, along with nausea and vomiting, a consistent early feature of a healthy pregnancy.^(2-4)

      3. Persons with or at increased risk of developing unhealthy high cholesterol levels

A lipid profile showing high levels of small, dense LDL cholesterol, particularly combined with the smaller size versions of HDL cholesterol, indicates significantly increased risk for cardiovascular disease. If your cholesterol profile shows you are at increased risk, you should drink only filtered coffee.

Epidemiological studies have linked consumption of boiled, but not filtered, coffee with increased risk for cardiovascular disease. Moderate daily consumption of filtered coffee, however, has not been associated with any adverse cardiovascular effects.

Why should unfiltered coffee increase CVD risk while filtered coffee does not? Coffee contains two diterpene compounds, cafestol and kahweol, which promote an increase in blood levels of cholesterol but are removed when the coffee is filtered.⁽⁵⁾

Top Foods with Caffeine

The following table lists the caffeine content of common beverages, food and drugs:

*Tea contains more caffeine than coffee by dry weight, but a typical serving of tea contains far less because tea is normally brewed more weakly than coffee. The longer you let your tea steep, the more caffeine it will contain. Also, the caffeine content varies by type of tea, and color is not an indicator of how much caffeine a tea contains. The pale Japanese green tea, gyokuro, for example, contains way more caffeine than much darker teas, like lapsang souchong, which contain little. ⁽⁶⁾ 

Is Coffee Bad For Your Bones?

Caffeine intake greater than 300 milligrams/day has been associated with increased urinary calcium excretion and increased risk of fracture, but several disclaimers accompany this finding. Is there logic to caffeine and osteoporosis?

Although high caffeine intake (greater than 300 milligrams per day) does increase the amount of calcium excreted in the urine, and the risk for osteoporosis-related fractures was significant among women consuming 4 or more cups of coffee per day, this increase in risk was seen only in those with calcium intakes less than 700 millligrams per day. If you’re taking AlgaeCal Plus, you’re getting 720 milligrams of calcium just from this supplement, and most of us get at least another 400 milligrams/day from our diet. ⁽⁷⁾ 

Research has shown that higher caffeine intake along with low calcium and milk intake, soda consumption, and heavy cigarette smoking all negatively affect bone mineral density. ⁽⁸⁾

However, caffeine actually has the smallest effect on calcium loss of any of the interacting compounds that cause calcium to be lost in your urine.

A cup of brewed coffee causes 3 milligrams of calcium to be lost in urine. This effect is so small that it is more than adequately offset by a tablespoon or two of milk in your coffee. A café au lait (latté) or cappuccino produces a substantial net gain in calcium, despite their caffeine content. ⁽⁹⁾

Caffeine’s small increase in calcium loss is due, at least in part, to the effect of high caffeine intake on the secretion of parathyroid hormone (PTH). ⁽¹⁰⁾ A cup of coffee typically contains around 100 milligrams of caffeine. Researchers found that consumption of one cup of coffee had no effect on PTH secretion, but 5 cups of coffee (~500 milligrams of caffeine) resulted in a significant 10.4% decrease in PTH secretion and also in PTH gene expression. Caffeine is quickly absorbed after digestion and has a half-life of 2.5- 4.5 hours, so if someone is drinking 5 cups of coffee over the course of the day, the 500 milligram dose of caffeine consumed could inhibit PTH secretion.

The key question to ask here is: “Is inhibiting PTH a bad thing for your bones?” And the answer is: “Probably not if you’re postmenopausal.”

Our parathyroid glands secrete PTH when calcium levels in our blood drop too low. To put more calcium into our bloodstream, PTH increases our kidney’s production of 1,25-D (the hormonal form of vitamin D that increases our absorption of calcium from our intestines). This sounds like a good thing, but, PTH also increases the activity of our osteoclasts, the specialized cells that break down bone, so our bones can release the calcium they contain into the bloodstream to raise its level in the blood. The end result: hyperactive PTH glands cause bone loss.

AND PTH secretion tends to become hyperactive as we age and is very frequently seen in elder women. The combination of insufficient calcium intake (postmenopausal women need 1,200 – 1,500 milligrams each day), deteriorating vitamin D status (men and women make less vitamin D from sun exposure as we age), reduced calcium absorption (we need vitamin D to absorb calcium effectively), and the impaired kidney conservation of calcium (kidney function also deteriorates with age) often seen in elders leads to overactive parathyroid glands and thus, increased bone resorption.

Bottom line: Lessening PTH secretion may be yet another way in which the caffeine in your morning cup of coffee protects your bones.

If you want to protect your bones against calcium loss, don’t give up coffee, focus on cutting back on your sodium intake. Sodium and calcium share the same transport system in the kidneys’ proximal tubule, and every 2,300 mg sodium excreted by the kidney also pulls 20 to 60 milligrams of calcium out with it. Get those sodium-laden processed foods out of your refrigerator, out of your freezer, out of your pantry and out of your life!⁽¹¹⁾

And quit taking Tums or other aluminum-containing antacids. These can increase the amount of calcium excreted in your urine by a whopping 50 milligrams/day or more!⁽¹¹⁾

For additional information on coffee and bone health, watch the video below or read the transcript, here.

The 9 Health Benefits of Coffee

With the three coffee caveat exceptions, coffee is one of your bones’ best friends.

Fortunately, those of us who need to avoid caffeine can enjoy decaffeinated coffee, which still contains highly protective, highly anti-inflammatory compounds that may help prevent type 2 diabetes, several types of cancer, including breast cancer, and Alzheimer’s disease – as well as osteoporosis.

And coffee REALLY helps.

• Coffee Protects Against Diabetes

Diabetes is a highly inflammatory condition that greatly promotes bone loss. Data gathered on 88,259 women in the Nurses’ Health Study II found that coffee drinkers lowered their risk of type 2 diabetes by 13% if consuming 1 cup per day, 42% for 2-3 cups per day, and 47% for 3 cups per day, compared to non-coffee drinkers. Women who drank 4 or more cups of coffee daily had a 50% lower risk of type 2 diabetes!

And the coffee didn’t have to be caffeinated. These reductions in disease risk were similar for those drinking decaffeinated as well as caffeinated coffee, filtered coffee, and even instant coffee.⁽¹²⁾ 

• Coffee, But Not Tea, Protects Against Breast Cancer

Premenopausal women drinking at least 4 cups of coffee a day were found to have a 40% reduction in risk of breast cancer, but no clear associations were seen between breast cancer risk and intake of black tea (which also contains caffeine) or decaffeinated coffee. Something else about coffee in addition to its caffeine content — most likely its rich concentration of phytonutrient compounds with strong antioxidant and anti-cancer actions (discussed below) — is responsible.⁽¹³⁾ 

• Coffee Protects Against Cognitive Decline

In the 10-year FINE study, older men drinking 3 cups of coffee daily had a rate of cognitive decline half that of the men who never drank coffee. The cognitive decline seen in coffee drinkers was 4.3 times smaller than the decline in non-consumers.⁽¹⁴⁾

Just this month, June 2016, a meta-analysis of 11 prospective studies, including 29,155 participants, found significant inverse association between highest coffee consumption and the risk for Alzheimer’s disease – a 27% reduction in risk! Coffee may help prevent Alzheimer’s because caffeine blocks the adenosine receptor, thus preventing the damage caused by β-amyloid, the toxic peptide that accumulates in the brain of patients with AD. Findings from one animal study demonstrated that caffeine intake at the human equivalent of 500 milligrams of caffeine (5 cups/day of coffee) could protect against or treat AD in a mouse model.⁽¹⁵⁾ 

• Coffee Protects Elders Against Cardiovascular Disease

If you’re over 65 and don’t have high blood pressure, daily coffee consumption may offer protection against cardiovascular disease as well as cognitive decline. Data collected for the first National Health and Nutrition Examination Survey Epidemiological (NHANES I) by James Greenberg and colleagues at the City and State Universities of New York (American Journal of Clinical Nutrition, 2007, 85 (2): 392- 398), revealed that those over 65 with normal blood pressure who drank at least 4 caffeinated beverages a day had a 53% reduced risk of death from cardiovascular disease. However, no cardiovascular benefit was seen from coffee consumption in participants with stage 2 hypertension or in those younger than 65.⁽¹⁶⁾

A further epidemiological study by Greenberg et al. tested the protective association they had found between coffee consumption and reduced risk of death from cardiovascular disease by looking at data collected on 1,354 subjects aged 65.4 to 96.6 years at study entry in the Framingham Heart Study population. Study participants were followed for 10.1 years. Coffee consumption was highly protective even for subjects with moderate to high blood pressure (systolic blood pressure (BP) <160 mm Hg and diastolic BP <100 mm Hg – normal BP is defined as 120 over 80; healthy BP is probably closer to 110 over 70). The decrease in risk of death from coronary heart disease for any caffeinated coffee versus none was 43%! And appeared to be due to caffeinated coffee consumption’s preventing the development or progression of heart valve disease.⁽¹⁷⁾

• Coffee Can Boost Your Athletic Performance

The caffeine naturally present in coffee, while potentially harmful for the caffeine-sensitive, may give athletes who tolerate caffeine a significant edge. A small study by UK researchers suggests that caffeine may not only improve alertness, but may boost carbohydrate delivery to cells by up to 26%, enhancing available energy and therefore improving physical performance.

Sophie Yeo and colleagues from the Human Performance Laboratory, School of Sport and Exercise Sciences, University of Birmingham, tested caffeine’s effects on 8 male endurance road cyclists. The cyclists underwent 3 two-hour exercise sessions, cycling at approximately 64% of their maximum output.⁽¹⁸⁾

During each session, the cyclists consumed one of three beverages. All beverages tasted the same, but one contained sugar (glucose), another contained glucose and caffeine, and the third, a control drink, was flavored water (no calories or caffeine). Samples of blood and expired air were taken from the athletes at 15 minute intervals to measure how quickly they absorbed and utilized the carbohydrate. When drinking the beverage containing caffeine, the athletes’ carbohydrate oxidation (ability to burn sugar to produce energy) increased by 26%. So, add a little sweetener — I prefer honey since it provides other benefits besides glucose— to that morning cuppa before your early morning workout and boost your performance.

• Coffee Lowers Risk of Death From All Causes

The results of a very impressive study showing coffee helps lower risk of what is referred to in the medical literature as “all-cause mortality” (translated into English, this means death from all causes) was published in the New England Journal of Medicine, May 2012.⁽¹⁹⁾

This was a very large study – involving 229,119 men and 173,141 women participants in the National Institutes of Health-AARP Diet and Health Study, and aged 50 to 71 years of age at baseline. When the researchers compared risk for death among men who drank coffee compared to those who did not, they found it was 10% lower for men drinking 2-3 cups of coffee daily, and 12% lower for men drinking 4-5 cups each day. Among women, the reduction in risk of death from all causes was even greater: 13% for 2-3 cups and 16% for 4-5 cups a day.

• Coffee Does NOT Increase Fracture Risk

Study after study has been done to try to show that coffee is problematic for bone – but the results of all these studies keep failing to find any evidence to support this fear. In fact, the findings are all just the opposite.

The two most recent papers evaluating the effect of drinking coffee on bone health to appear on PubMed are a study conducted by Swedish researchers that was published in the American Journal of Epidemiology in 2013, and another conducted by Korean researchers that was published in the journal Korean Family Medicine in 2014.

The Swedish researchers looked at whether drinking coffee over many years was related to an increased risk of fracture or a decrease in BMD. Their analysis included data on 61,433 women who were born sometime between 1914 and 1948 and were followed from 1987 through 2008.

There was no evidence of a higher rate of hip or any other type of fracture even with increasing coffee consumption. A high coffee intake (≥4 cups daily) versus a low intake (<1 cup daily) was associated with a very small reduction in bone density that did not translate into an increased risk of fracture.⁽²⁰⁾

The Korean researchers evaluated the effects of coffee consumption on bone mineral density in Korean premenopausal women. The authors obtained the data from the fourth Korea National Health and Nutrition Examination Survey 2008–2009, which consisted of 1,761 Korean premenopausal women.

As usual, they found that coffee consumption showed no significant association with the bone mineral density of either the femoral neck or lumbar spine.⁽²¹⁾

The author of a companion article in the same journal issue advised limiting coffee consumption to 3 cups per day since more might (and I emphasize the “might” given all the research on coffee showing its many beneficial effects) be a problem IF calcium intake is inadequate.⁽²²⁾

• Coffee Lowers Your Risk of Degenerative Diseases

How does coffee lower your risk for degenerative diseases, including osteoporosis?

Coffee is loaded with superstar phytonutrients, two of which — caffeic acid and chlorogenic acid – protect the special cells in the pancreas that produce and secrete insulin.

In addition to caffeic acid and chlorogenic acid, other constituents in coffee — 5-O-caffeoylquinic acid (CGA) and N-methylpyridinium (NMP) – trigger the activation of a key antioxidant pathway –the Nrf2/antioxidant-response element (ARE) detoxifying pathway. Nrf2-regulated genes include those responsible for the production of our most important antioxidant enzymes – the glutathione S-transferases (GST). Boettler U, Volz N, Pahlke G, et al. Coffees rich in chlorogenic acid or N-methylpyridinium induce chemopreventive phase II-enzymes via the Nrf2/ARE pathway in vitro and in vivo.⁽²³⁾

Coffee increases your production of adiponectin, a hormone secreted by fat cells that is involved in regulating blood sugar levels and burning fatty acids.  Higher levels of adiponectin are protective against not just type 2 diabetes, but obesity, atherosclerosis, and non-alcoholic fatty liver disease (NAFLD). If you’ve read Your Bones, you know that each of these diseases chronically increases inflammation and thus increases the activation of osteoclasts and your risk for excessive bone loss and osteoporosis.⁽²⁴⁾

Coffee lowers another hormone secreted by fat cells that promotes inflammation called leptin. Chronically-elevated leptin levels are associated with obesity, overeating, and inflammation-related diseases including type 2 diabetes, cardiovascular diseases, and – yet again — osteoporosis.⁽²⁴⁾

Coffee also lowers another marker of inflammation called high sensitivity C-reactive protein (hs-CRP). High levels of hs-CRP indicate a body experiencing relentless chronic inflammation, with widespread adverse effects, just one of which is the excessive activation of osteoclasts that results in ramped up bone loss.⁽²⁴⁾

Based on serving size or daily units, coffee contains larger amounts of all these bone-protective phytochemicals than tea or red wine.⁽²⁵⁾

How large a supply of protective phytochemicals coffee delivers is indicated by the fact that drinking just one cup of coffee (200 mL—about 7 ounces) greatly increases our LDL cholesterol’s ability to resist being damaged by free radicals – which is the first step in the development of atherosclerosis. Coffee’s protective effects on cholesterol result from of the incorporation of coffee’s phenolic acids into LDL.⁽²⁶⁾

Animal studies may explain why coffee helps us keep our brains in good working order as we age. In mice with the rodent equivalent of Alzheimer’s disease (amyloid-beta induced brain cell atrophy), one of the active compounds in coffee beans, trigonelline, has been shown to regenerate brain cells (dendrites and axons), resulting in memory improvement.⁽²⁷⁾

• Coffee Contains Small Amounts of Key Bone health Minerals

Coffee isn’t a great source of minerals, but as a plant-based drink, it contains some, and can help contribute to our intake of a few that we need to be getting more of if we want to have healthy bones.

Let’s start with magnesium. A cup of coffee contains about 7 mg, which is a drop in the daily-requirement bucket (420 mg for men, 320 mg for women). But because we don’t eat enough fruit, vegetables, and whole grains, the average American’s intake falls about 100 mg short of the daily goal. Two cups of coffee can help close that gap by 14%.

A cup of coffee provides about 116 mg of potassium, which can help offset some of the negative consequences of the excessive amounts of sodium in all the processed foods most of us eat. At about 116 mg of potassium per cup, coffee’s contribution toward the 4,700 mg of the potassium that we’re supposed to get daily is tiny, but it’s something. A cup of coffee also has small amounts of niacin (0.5 mg) and choline (6.2 mg).

It’s true that coffee can slightly increase urinary excretion of calcium, but this can easily be more than counter-balanced by enjoying your coffee with some form of calcium-containing milk and/or taking a good calcium supplement + ensuring your vitamin D (25[OH]D levels are in good range (60-80 ng/mL).

If you’re taking AlgaeCal Plus, you’re covered with 720 milligrams of calcium and 2,000 IU of D3 provided in a daily serving.

Caffeine and Osteoporosis – The Final Verdict

Keep your caffeine take to no more than 300 milligrams/day, but enjoy your coffee guilt free.

Coffee’s numerous beneficial effects have been repeatedly and clearly substantiated. Coffee clearly protects us against inflammation via numerous mechanisms – and anything that helps prevent chronic inflammation will help lessen your risk for osteoporosis. Ensure your calcium intake is adequate – take your coffee with a little cow’s milk or calcium-enriched soy or other calcium-enriched non-dairy milk, take your AlgaeCal Plus, and enjoy your coffee!

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Caffeine Content of Drugs and Foods, Center for Science in the Public Interest Table,  http://www.cspinet.org/new/cafchart.htm?gclid=Cj0KEQjws_m6BRCv37WbtNmJsIBEiQAWKKt0GPkWATkRqHij2oV9qIEh09Mwpgx_elyz1LtfW-nDZAaAvZJ8P8HAQ