The focus of this blog is to outline nutritional strategies for building strong and sturdy bones, while at the same time keeping arteries soft and supple.
James H O’Keefe MD, James J DiNicolantonio PharmD, Loren Cordain PhD. | PHOTO: EVOLUTION INSTITUTE
At a glance
One of every two Americans will develop weak bones (osteoporosis) in her or his lifetime. Bone fractures are occurring more commonly among both young and old. For people over age 65 fractures are the most common cause of hospitalization, nursing home admission, and death.
Only 30% of the US population consumes the Recommended Daily Allowance (RDA) of calcium, which is 1,000 to 1,200 mg daily.
Calcium is ideally obtained from dietary sources, but about 70% of the calcium in the diet of the average US adult comes from dairy. However, many people (especially those who are lactose intolerant) feel better when they avoid dairy, and high milk consumption has been associated with several diseases. Yet, people who avoid dairy are generally consuming inadequate amounts of calcium.
It is best to supplement only the nutrients for which one is deficient. Unfortunately, standard calcium supplements may lead to calcification of arteries and coronary disease.
Adult human hunter-gatherers consumed most of their calcium in the form of bones from animals, including small and large mammals, birds, fish and reptiles. Indeed through millions of years of evolution, we are genetically adapted to consume a large proportion of our dietary calcium from bones, where calcium is absorbed along with a matrix of bone-building nutrients. Even so, bone consumption adequate to fulfill the calcium needs in is impractical today.
Organic bone meal, when food, may provide an ideal strategy to ensure adequate dietary calcium. Microcrystalline hydroxyapatite (the form of calcium found in bones and bone meal) unlike standard calcium supplements, doesn’t cause an acute spike in blood calcium levels, and thus does not appear to calcify arteries or increase risk of heart attack. Placebo controlled randomized trials show that calcium from bone meal in combination with vitamin D increases bone thickness, whereas standard calcium supplements at best only cause a slowing of further bone loss.
Generous intake of vegetables and fruits will alkalinize the system, and may promote both bone strength and CV health.
Diets containing a moderate amount of animal protein are linked to greater bone mass and fewer fractures, especially if the calcium intake is also adequate (about 1,000 mg of calcium per day).
Vitamin K and magnesium also appear to improve both bone and heart health.
INTRODUCTION
Calcium is the most ubiquitous mineral in the human body. An average sized adult body contains approximately 1,000 g to 1,200 g of calcium, which is mostly incorporated into bones and teeth as crystals of calcium-hydroxyapatite [Ca10(PO4)6(OH)2]. Calcium also circulates throughout the blood and soft tissues, where it plays fundamental roles in cell conduction, muscle and brain function, hormone regulation, and in the function of the heart and blood vessels.
Only 30% of the US population consumes the Recommended Dietary Allowance (RDA) of calcium, which is 1,000 to 1,200 mg daily. The body will demineralize its own skeletal system to maintain blood calcium levels in situations where calcium intake and/or retention are insufficient.1
OSTEOPENIA/OSTEOPOROSIS – AN EPIDEMIC OF WEAK BONES
Typically about 2-4% of an adult’s skeleton is remodeled each year. This involves a process wherein osteoclasts breakdown bone and osteoblasts rebuild it. However, in the presence of catabolic factors such as suboptimal nutrition, abnormal hormone levels, sedentary lifestyle, stress and aging, the body leaches calcium and other minerals from the bone creating tiny holes or pores (hence the term osteoporosis), which renders the bones weak and brittle, especially if collagen protein is also being lost. Starting at about age 50, post-menopausal women lose about 0.7% – 2% of their bone mass each year while men over age 50 lose 0.5% – 0.7% yearly. Between ages 45 – 75, women on average lose 30% of their bone mass, whereas men lose 15%.
According to the US Surgeon General’s Report, 1 in 2 Americans over age 50 is expected to have or to be at risk of developing osteoporosis, which causes about 9 million fractures annually.2 Among women over age 45 osteoporosis accounts for more days spent in hospital than many other diseases such as diabetes, myocardial infarction (MI), chronic lung disease, and breast cancer.3 Additionally, strong associations exist between decreased bone mineral density and cardiovascular (CV) death. Fragility fractures are the primary cause of hospitalization and/or death for US adults ≥ age 65.2 Furthermore, 44% of nursing home admissions are due to fractures.2 However, the drugs used to strengthen bones are expensive and carry potential serious side effects.
A Mayo Clinic study reported that compared to 30 years ago, forearm fractures have risen more than 32% in boys and 56% in girls. The authors concluded that dietary changes including insufficient calcium and excess processed food were partly responsible for the increased fractures.4
THE DAIRY DILEMMA
Dairy foods and beverages account for about 70% of all dietary calcium intake among Americans. Legitimate concerns exist regarding potential deleterious effects of cow’s milk on health.5-10 Dairy foods, on an evolutionary time scale, are relative “new-comers.”11 Domestication of cattle, sheep and goats first occurred approximately 11,000 to 10,000 years Before Present (BP).12-15 Moreover, 65% of the worldwide population is lactose intolerant due to loss of ability to make the lactase enzyme as an adult.16
Figure 1: Increasing milk intake significantly increased multi-variable adjusted risk for total mortality during follow up.17
An impressive new study of over 106,000 adults followed for 20 years showed that people who were drinking three or more glasses of milk per day had increased risks for bone fracture and higher mortality rates compared to the individuals drinking not more than one glass of milk per day.17 The overconsumption of milk has been inconsistently associated with cataracts, ovarian and prostate cancers, and Parkinson’s disease as well as autoimmune diseases such as type 1 diabetes and multiple sclerosis.18-20 The sugar in milk, lactose, is broken down in GI tract to D-galactose and D-glucose. D-galactose has been found to increase inflammation and oxidation in adult humans, and in adult animals this sugar triggers accelerated aging, neuro-degeneration, and a shortened life span.17
Thus, cow’s milk, though rich in many nutrients including calcium, has issues that render it less than ideal as a dietary staple for adults. On the other hand, fermented dairy such as yogurt and cheese appears to be safer than milk, possibly because the D-galactose has been broken down and is either in much lower quantities or no longer present.17
Table 1.
PLANT-BASED DIETARY SOURCES OF CALCIUM AND PROTEIN: EFFECTS ON BONE HEALTH
Most vegetarians, especially vegans, consume inadequate amounts of calcium, and also they absorb a smaller proportion of this important mineral because of the oxalic and phytic acid contained in many plant, grain, and legume products.21 Not surprisingly bone fractures are more common in vegetarians and are strikingly higher in vegans.22-26 Of note, some low-oxalate plant foods such as kale and other cruciferous vegetables are relatively high in calcium, and exhibit excellent calcium absorption as well.27 Still, a large serving of kale contains only 100 mg of calcium.
DIETARY PROTEIN, CALCIUM AND BONE HEALTH
Some older studies suggested that the acid load generated from metabolizing animal protein might predispose to bone loss.28-29 However, more recent studies show that adequate intake of animal protein is beneficial to bone health.30-33 Hunter-gatherer diets, though rich in animal protein, are also high in vegetables and fruits, as well as calcium from ingested bones, leafy greens and nuts. This combination of foods in the evolutionary diet helped to build the robust bone health generally seen among people following this ancestral forager style of diet.11, 34 In contrast, the processed foods, grains, sugar and dairy foods abundant in the modern diets tend displace fruits and vegetables, thereby shifting the metabolic effects of the diet from alkaline to acid, which predisposes to compromised bone health.35-38
Figure 2: A diet that contains moderate amounts of fresh lean animal protein, when combined with adequate calcium intake, promotes bone strength and reduces fracture risk. In contrast, high protein diet with inadequate calcium intake increases risk of fracture.31
Increased animal protein intake and bone ingestion both raise levels of insulin-like growth factor-1 (IGF-1), which is anabolic and helps build bone.39-40 A growing body of evidence indicates that diets higher in animal protein produce greater bone mass and fewer fractures, particularly if the calcium intake is also adequate (about 1,000 mg of calcium/day).30-31, 41 Thus, a diet providing ample dietary calcium, along with alkalizing foods as fruits and vegetables and possibly also alkaline mineral waters may create a milieu wherein moderate intake of animal protein contributes favorably to bone health.42-43
CALCIUM: MAGNESIUM RATIO
Accumulating evidence indicates that magnesium acts as a protective agent against soft tissue calcification and may reduce risk of cardiovascular disease.44-45 Moreover, a diet rich in magnesium may reduce risk for both diabetes and high blood pressure.46-48 Importantly, magnesium deficiency seems to predispose to osteoporosis, inflammation and increased risk of pathological blood clots.49 Optimal dietary magnesium intake is about 7 to 10 mg/kg/ day, ideally with approximately a 2:1 calcium-to-magnesium ratio, preferably in the context of an alkaline diet, since an acid-producing diet increases excretion of both magnesium and calcium.50
VITAMIN K IMPROVES BOTH BONE AND CV HEALTH
Emerging evidence suggests that vitamin K may bestow protective effects upon both the skeletal and CV systems. Vitamin K is found in multiple forms, including vitamin K1 and vitamin K2. The main dietary sources for vitamin K1 are green leafy vegetables. The major sources of vitamins K2 in Western populations are fermented foods, especially cheese and curds.51-52 Multiple large and impressive studies show that low dietary intake of vitamin K1 is associated with weak bones and increased fracture risk.53-54 A recent meta-analysis concluded that supplementation with vitamin K1 and K2 improved bone health, and resulted in a 60% lower risk of fractures.55
In general, normal healthy calcification is restricted to bone, teeth and nails, whereas calcification elsewhere in the body such as in the arteries and soft tissues is regarded as pathological. Increased vitamin K2 intake has been linked to decreased arterial calcium deposition.56-57 In two different randomized, double-blind controlled trials, supplemental vitamin K2 has been shown to significantly delay both the development of coronary artery calcification and prevent abnormal stiffening of the blood vessels that comes with age.58-59
CALCIUM SUPPLEMENTATION AND BONE HEALTH
Approximately 60% of middle-aged US women regularly use calcium supplements,60 which at best tend to only slow further bone loss, but do not build bone. In large meta-analyses calcium supplementation was only effective for preventing hip fractures when it was combined with vitamin D.61-62 Studies show that supplemental vitamin D, not supplemental calcium, might be the more important predictor of bone mineral density.63 Indeed vitamin D plays a major role in both intestinal calcium absorption and bone health.64 Mono-supplementation with calcium, especially using the most commonly prescribed formulations (calcium carbonate and calcium citrate) might drive down the absorption of phosphate, thereby contributing to bone demineralization secondary to abnormal calcium to phosphate ratios.65 The recently updated US Preventive Services Task Force (USPSTF) has stated that there is insufficient evidence that standard calcium supplementation prevents fractures in premenopausal women or in men.66
STANDARD CALCIUM SUPPLEMENTS MAY INCREASE CARDIAC RISK
The traditional focus in nutrition based upon supplementation of single isolated nutrients may be especially misguided in the case of calcium and bone health. A diet supplemented with calcium as a mono-nutrient pill is not ideal for promoting bone health and may instead accelerate arterial plaque growth and vascular calcification, and increase risk of MI.
Figure 3: Percentage of women who were randomized to calcium supplement or placebo who suffered a MI during the study.67
A randomized trial showed that calcium supplementation increased risk of myocardial infarction (MI) in women by 30%.67 A subsequent meta-analysis of placebo-controlled trials involving 36,000 female subjects also found that traditional calcium supplements significantly increased risk of MI.1 Another recent prospective study of 388,229 men and women with a 12-year follow-up showed that calcium supplementation was associated with elevated risk of heart disease death in men, but not in women.68
Traditional calcium supplements Increase CV risk probably by causing calcification and constriction of arteries in addition to arterial plaque formation.60, 69-71 The amount of calcium in the walls of coronary arteries is among the strongest independent predictors of cardiac risk.72 Several studies show that consuming 500 to 1,000 mg of a standard calcium supplement will cause an abnormal spike in one’s serum calcium level.73-75 In contrast, calcium intake from ingestion of bones or bone meal (calcium hydroxyapatite) results in much less drastic changes in circulating calcium levels.73
BONES AND BONE MEAL AS IDEAL SOURCES OF CALCIUM
A moderate amount of calcium from food sources does not appear to increase the risk of vascular disease.76 In a prospective cohort study with a mean follow-up of 19 years, the optimal amount of dietary calcium for reducing coronary risk long-term was about 1,000 mg per day. In that study dietary calcium intakes of less than 700 mg/day or more than 1,400 mg/day were associated with increased risk of coronary disease and higher death rates.60
Figure 4: Relationship of daily calcium intake to risk of CV mortality during follow up. Data were fully adjusted of confounding variables.60
A plant-rich, grain-free diet alters the acid-base status so as to be slightly alkaline, which is conducive for bone health. However, plants (with the exception of some oxalate-free leafy vegetables, such as kale) are relatively poor sources of calcium compared to animal sources such as dairy products and animal bones. We suspect that dairy, though an excellent source of bioavailable calcium, be problematic for adverse health effects for many people.
Adult human hunter-gatherers consumed most of their calcium in the form of bones from animals, including small and large mammals, birds, fish, reptiles etc.77 Indeed through millions of years of evolution, we are genetically adapted to consume a large proportion of our dietary calcium from bones, where calcium is absorbed along with a matrix of nutrients including magnesium, phosphorus, strontium, zinc, iron, copper, collagen protein, aminoglycans, and osteocalcin—all of which also support robust bone formation.78 Theoretically, including animal bones (sardines, salmon, soft chicken bones, bone broths, etc.) is an attractive dietary strategy to ensure adequate calcium intake and to optimize long-term bone health. However, it is difficult to consume 1,000 mg per day of calcium by eating bones. For example, one can (3.5 oz.) of sardines (with bones) provides about 250 mg of calcium, and an 8 oz. serving of bone broth contains only 70 mg of calcium.
Bone meal, when taken with food, may provide a more practical means to ensure adequate calcium intake without causing calcification of the arteries or predisposing to CV disease. Ingestion of microcrystalline hydroxyapatite (the form of calcium found in bone) produces less of an acute spike in blood calcium levels compared to soluble calcium salts typically used in standard supplements, and thus may be less likely to increase vascular calcification and coronary risk.79 Hydroxyapatite also stimulates the osteoblast cells that build bone. Bone and or bone meal when ingested provide virtually all of the essential building blocks needed to construct bone tissue.
Figure 5: Change in cortical bone thickness among 64 women with osteopenia randomized to 14-months of treatment with three different treatments. The hydroxyapatite therapy was the only one to show increased bone thickness (p 80
In a placebo controlled randomized trial women who took 1,000 mg of calcium in the form of hydroxyapatite in conjunction with oral vitamin D showed a significant increase in bone thickness whereas those who took 1,000 mg of a standard calcium carbonate supplement did not.80 A different double-blind placebo-controlled study found that supplementing with hydroxyapatite and vitamin D3 significantly improved markers of bone health.10 The addition of vitamin K2 and magnesium to an organic bone meal supplement should further enhance its effectiveness and reduce the risk of soft tissue calcification.
Supply What’s Missing
CardioTabs BONE Essentials is a highly absorbable, natural calcium sourced product containing MicroCrystalline HydroxyApatite (MCHA). MCHA provides essential minerals in an organic, collagen-rich protein milieu and has been clinically demonstrated to not spike blood calcium levels the way other forms of calcium, such as carbonate and citrate, can. Vitamin D3, vitamin K2, potassium and other key nutrients are combined with MCHA for support of stronger bones and more youthful cardiovascular and arterial health.
*HEALTH CLAIM: Adequate calcium and vitamin D as part of a well balanced diet, along with physical activity, may reduce the risk of osteoporosis.
James H O’Keefe MD, Saint Luke’s Mid America Heart Institute, Kansas City, Missouri
James H O’Keefe, MD, is a cardiologist and Medical Director of the Charles and Barbara Duboc Cardio Health & Wellness Center at Saint Luke’s Mid America Heart Institute. He is a Professor of Medicine at the University of Missouri-Kansas City. His postgraduate training includes a cardiology fellowship at Mayo Clinic in Rochester, Minnesota. Dr. O’Keefe is board-certified in Cardiology, Internal Medicine, Nuclear Cardiology, and Cardiac CT Imaging. He is consistently ranked among the regional ‘Top Doctor’ lists and has been named as one of USA Today’s Most Influential Doctors. Dr. O’Keefe has contributed more than 250 articles to medical literature and has authored best-selling cardiovascular books for health professionals including: The Complete Guide to ECGs, Dyslipidemia Essentials, and Diabetes Essentials. He lectures extensively on the role of therapeutic lifestyle changes and drug therapy in cardiovascular risk reduction. Dr. O’Keefe has co-authored, with his wife Joan, the best-selling consumer health book, The Forever Young Diet and Lifestyle. He is actively involved in patient care and research.
Pedro Carrera-Bastos MS, Department of Clinical Sciences, Center for Primary Health Care Research, Lund University/Region Skåne, Malmö, Sweden
Pedro Bastos provides consultations, research, and advice to The Paleo Diet community. He is a member of the New York Academy of Sciences, the International Society for the Study of Fatty Acids and Lipids, and the Nutrition Society. Pedro is a certified personal trainer and strength and conditioning instructor, and he holds post-graduate diplomas in exercise and health (from School of Sport Science of Rio Maior, Portugal) and in biochemistry and orthomolecular medicine (from Fernando Pessoa University, Portugal). He received his master’s degree in human nutrition and food quality through Universitat de les Illes Balears (Spain). His research interests are dairy products and human health, nutrition and chronic inflammatory/auto-immune diseases, role of micronutrients in human health, prevention of osteoporosis and sarcopenia, nutrition and liver adenomas, and the role of nutrition in sports injury prevention.
Maelan Fontes-Villalba MS, Department of Clinical Sciences, Center for Primary Health Care Research, Lund University/Region Skåne, Malmö, Sweden
Maelan Fontes is a member of the Developmental Origins of Health and Disease Society and the Psychoneuroimmunology Research Society. He also lectures in Clinical Psychoneuroimmunology at the Unversitat de Girona in Spain. In addition to his graduate degree in physiotherapy, and his post-graduate degree in clinical psychoneuroimmunology, Maelan has studied and taught Nutrition as Medicine: Pain; Resoleomics; Neurotraining; Nutrition as Medicine: Detoxification; Auriculotherapy (Neurobiopsychology); and Nutrition as Medicine: Infant Nutrition.
James J DiNicolantonio PharmD, Saint Luke’s Mid America Heart Institute, Kansas City, Missouri
Dr. DiNicolantonio is a cardiovascular research scientist at the Saint Luke’s Mid America Heart Institute. His research focuses on cardiovascular health and disease—specifically, diabetes, obesity, hypertension, lipids, antithrombotics, anticoagulants, as well as nutrition and nutritional supplements. He is the author or co-author of over 120 medical publications, encompassing opinion pieces, review articles, and systematic reviews and meta-analyses. Dr. DiNicolantonio has testifed in front of the Canadian Senate on the harms of added sugars, and has published several high-profile articles in peer-reviewed journals related to nutrition, including an opinion piece in The New York Times on sugar addition. Dr. DiNicolantonio also serves as the Associate Editor of British Medical Journal’s (BMJ) Open Heart, which is published in partnership with the British Cardiovascular Society. He’s also a frequent reviewer for several medical journals and is on the editorial advisory board of several medical journals including the International Journal of Clinical Pharmacology & Toxicology (IJCPT), CIP Journal of Cardiology, and Progress in Cardiovascular Diseases. Dr. DiNicolantonio graduated from the University at Buffalo School of Pharmacy in 2010. He frequently collaborates on research initiatives with James O’Keefe, M.D., a cardiologist at the Mid America Heart Institute.
Nate Bergman, DO, Department of Geriatric Medicine, Cleveland Clinic Foundation. Cleveland, Ohio
Nate has been passionate about proactive, preventive, and participatory medicine since his days as a research fellow at the NIH. Currently, he is completing a fellowship in geriatric medicine with emphasis on functional medicine and the aging brain at the Cleveland Clinic. He lives in Cleveland with his wife and their four young children.
Loren Cordain PhD, Professor Emeritus of Nutritional Science, Colorado State University, Fort Collins, Colorado
Dr. Loren Cordain is Professor Emeritus of the Department of Health and Exercise Science at Colorado State University in Fort Collins, Colorado. His research emphasis over the past 20 years has focused upon the evolutionary and anthropological basis for diet, health and well being in modern humans. Dr. Cordain’s scientific publications have examined the nutritional characteristics of worldwide hunter-gatherer diets as well as the nutrient composition of wild plant and animal foods consumed by foraging humans. He is the world’s leading expert on Paleolithic diets and has lectured extensively on the Paleolithic nutrition worldwide. Dr. Cordain is the author of five popular bestselling books including The Paleo Diet, The Paleo Answer, and The Paleo Diet Cookbook, summarizing his research findings.