Tag Archives: calcium

Worried About Inadequate Calcium on Your Paleo Diet?

Bix at Fanatic Cook has a post on calcium and dairy consumption as regards to protection against broken hips from thin bones (osteoporosis). Or rather the lack of protection!

I’ve worried before that most paleo diets could be deficient in calcium because they don’t include milk products. Osteoporosis in adults or inadequate bone growth in kids are about the only significant problems you might see if that’s the case.

Bix quotes Harvard professor and pediatrician Dr. David Ludwig:

“Humans have no nutritional requirement for animal milk, an evolutionary recent addition to diet. Anatomically modern humans presumably achieved adequate nutrition for millennia before domestication of dairy animals, and many populations throughout the world today consume little or no milk for biological reasons (lactase deficiency), lack of availability, or cultural preferences.

Adequate dietary calcium for bone health, often cited as the primary rationale for high intake of milk, can be obtained from many other sources. Indeed, the recommended levels of calcium intake in the United States, based predominately on balance studies of 3 weeks or less, likely overestimate actual requirements and greatly exceed recommended intakes in the United Kingdom.

Throughout the world, bone fracture rates tend to be lower in countries that do not consume milk compared with those that do. Moreover, milk consumption does not protect against fracture in adults, according to a recent meta-analysis.”

Read the whole enchilada.

Another article mentions Dr. Ludwig:

People with a high-quality diet — those who get adequate protein, vitamin D and calcium from things like leafy greens, legumes, nuts and seeds — may get little or no added nutritional benefit from consuming three servings of dairy a day, Ludwig argues.

Hmmm. Wonder how he feels about grains. Sounds paleoish so far.

I’m just about ready to stop worrying about calcium.

Steve Parker, M.D.

Low Calcium Intake May Not Matter for Bone Health

paleobetic diet, diabetic diet, calcium

Modern “films” are digital

I’ve worried about the relatively low calcium content of most paleo diets. I see lots of little old ladies eating non-paleo with hip, spine, and wrist fractures related to the bone-thinning disease called osteoporosis. The bones break because they’re not adequately dense. Some experts think low calcium intake causes osteoporosis.

A Vietnamese study published in 2009 compared bone density of Buddhist nuns, who are vegans, with omnivorous controls. Dietary calcium content was 330 mg/day in the vegans, 682 mg/day in the omnivores. Nevertheless, bone density and osteoporosis prevalence were not significantly different between the groups. (Unfortunately, fracture rates were not reported.)

So perhaps the relatively low calcium content of paleo diets isn’t anything to worry about.

Steve Parker, M.D.

h/t Jamie Scott

CavemanDoctor On Calcium Consumption and Osteoporosis

paleo diet, Steve Parker MD,calcium, osteoporosis

I worry about her bones 50 years hence

I’ve fretted here before about possible inadequate calcium intake on typical paleo diets. Colin Champ, M.D., otherwise known as CavemanDoctor, has a way around it. A quote summarizes his ideas:

“In Review:

  1. Calcium levels and bone health are multifactorial and calcium intake is just the tip of the iceberg.
  2. Don’t count on dairy for calcium and instead get it naturally in highly absorbable forms in the foods nature laid out for you.
  3. Instead, avoid foods that result in decreased absorption and increased excretion of calcium like milk.
  4. Get some sun (not sun burns) or if that is not possible, take some vitamin D3.
  5. Lift heavy weights and sprint as the heavy loads stimulates bone mineralization and decrease bone breakdown.
  6. Avoid chronic stress and the increase in glucocorticoids that results.
  7. Increase your highly absorbable sources like green leafy vegetables, and decrease poorly absorbable sources like milk, and avoid its downside with its large amounts of lactose (sugar).
  8. Avoid large amounts of carbohydrates that cause significant insulin release and calcium loss in the urine.”

Read the rest.

Maybe We Don’t Need as Much Calcium As We Think

I’ve worried about the relatively low calcium amounts provided by most paleo diets.  Maybe I shouldn’t. Fanatic Cook Bix has a new post about various calcium absorption mechanisms in our bodies. If intake is low, certain mechanisms kick in, allowing us to absorb more than is usual. I quote:

So, someone who is eating less than 400 mg – which is half the recommended amount (the DRIs are 800-1000 mg/day, some groups recommend up to 1300 mg) – may, all else being equal, end up with a similar calcium status as someone eating 1000 mg or more because an active transport mechanism kicks in at lower intakes. As well, more calcium may be absorbed from the colon.

Calcium is not unusual in this regard. Absorption of nutrients is often higher when intake is low, and vice versa. Zooming in on one nutrient, in this case calcium, and fretting over whether we’re “getting enough” has a downside if it leads to taking supplements. Many nutrients compete for intestinal absorption, e.g. zinc supplements have been shown to substantially reduce calcium absorption. And, it should be said, what the body doesn’t absorb goes out with the feces.

It may be better to focus on eating a variety of minimally processed foods than to focus on discrete nutrients, and let the body take care of itself.

Read the rest.

At any given time, I usually have at least one little old lady on my hospital service who has fallen and fractured her hip, wrist, pelvis, or humerus (arm bone that’s part of the shoulder). Nearly always she has the bone-thinning disease called osteoporosis, which may be related to calcium consumption. If we can prevent osteoporosis with diet and exercise, that’s much preferable to dealing with the fractures.

Too Much Calcium May Be Worse Than Too Little

I’ve been fretting that the paleo diet may not provide enough calcium to keep aging bones strong. On the other hand, the writer(s) at the Joslin Diabetes Blog point out that too much calcium may promote cardiovascular disease.

The February, 2013, issue of British Medical Journal has a pertinent research report. The Joslin blogger writes:

Participants were women from a mammography cohort who were asked about their calcium consumption, using a food frequency questionnaire, at baseline and seven-to-ten years later. The 61, 433 women were followed for a period of 19 years. During that time, 6894 participants died of cardiovascular disease or stroke. The researchers found that the women taking over 1400mg of calcium per day had a higher incidence of cardiovascular disease. Participants whose calcium consumption remained within suggested bounds, between 600mg and 1000mg per day, did not appear to have a greater vulnerability to cardiac disease.

Read the rest.

I confess I haven’t read the BMJ article.

I always wonder about overall death rates when I see results like this. A group may have higher or lower rates of cardiovascular disease, and yet live longer than the comparison group. An intervention could prevent cardiovascular disease and cardiovascular death, yet increase the incidence of death from infection, cancer, accidents, or suicide, etc.

I bet a lot of adults eating a paleo-style diet approach or exceed 600 mg a day of calcium. I’m feeling better about the calcium in paleo diets. But I don’t want to have to depend on feelings.

The Joslin blogger notes that, “Perhaps it is time to have a conversation with your health care provider to determine what the best dose of calcium is for you.” Problem is, I’m not sure any healthcare provider really knows the best “dose” of calcium for the average person, whether supplemental or dietary calcium.

Sorry, men. These findings may or may not apply to you. At least you don’t have to worry about osteoporosis nearly as much as women.

Steve Parker, M.D.

PS: In case you hadn’t run across it elsewhere, note that taking a calcium supplement without a concomitant vitamin D supplement may be more harmful than taking calcium with vitamin D.

 

A Paleo Problem: Calcium

paleo diet, Steve Parker MD,calcium, osteoporosis

I worry about her bones 50 years hence

It appears difficult to meet the Recommended Dietary Allowance (RDA) for calcium while eating most versions of the paleo diet.  That’s because they don’t include milk products.  The Linus Pauling Institute at Oregon State University has a review of calcium as related to nutrition and health, last updated in late  2010. They say that few Americans hit their recommended daily calcium goal.

I see lots of little old ladies with hip and other fractures related to osteoporosis. Trust me, you don’t want to go there. It’s difficult to reverse osteoporosis, an insidious process that’s been going on for decades before the fracture.

Osteoporosis may be related to years of inadequate calcium consumption. Adequate vitamin D is  an important part of the equation, too. Blood calcium levels are strictly regulated, and if they’re too low, calcium is pulled from the bones to fill the blood’s tank.

Broccoli and bok choy are fair sources of calcium, but pale in comparison to milk. Bok choy isn’t a part of my diet; I’m not even sure I’ve ever had it. Below is a video on bok choy cooking. Looks simple enough.  I need to look into kale, too.

Many paleophiles promote bone broth, but I haven’t figured out why yet. Is it high in calcium? (Hat tip to Wendy Schwartz for the word “paleophile”.)

A can of sardines looks like a good source of calcium: 350 mg or 35% Daily Value.

Can you help me worry less about calcium deficiency?

My Critique of the Joslin Critique of the Paleo Diet

paleo diet, Paleolithic diet, hunter-gatherer diet

Huaorani hunter in Ecuador

The Joslin Diabetes Blog yesterday reviewed the paleo diet as applied to both diabetes and the general public.  They weren’t very favorably impressed with it.  But in view of Joslin’s great reputation, we need to give serious consideration to their ideas.  (I don’t know who wrote the review other than “Joslin Communications.”)

These are the main criticisms:

  • diets omitting grains and dairy are deficient in calcium and possibly B vitamins
  • you could eat too much total and saturated fat, leading to insulin resistance (whether type 1 or 2 diabetes) and heart disease
  • it’s not very practical, partly because it goes against the grain of modern Western cultures
  • it may be expensive (citing the cost of meat, and I’d mention fresh fruit and vegetables, too)

Their conclusion:

There are certainly better diets out there, but if you are going to follow this one, do yourself a favor, take a calcium supplement and meet with a registered dietitian who is also a certified diabetes educator  to make sure it is nutritionally complete, isn’t raising your lipids and doesn’t cause you any low blood glucose incidences.

Expense and Practicality

These take a back seat to the health issues in my view.  Diabetes itself is expensive and impractical.  Expense and practicality are highly variable, idiosyncratic matters to be pondered and decided by the individual.  If there are real health benefits to the paleo diet, many folks will find work-arounds for any expense and impracticality.  If the paleo diet  allows use of fewer drugs and helps avoid medical complications, you save money in health care costs that you can put into food.  Not to mention quality of life issues (but I just did).

Calcium and B Vitamin Deficiencies

This is the first I’ve heard of possible B vitamin deficiencies on the paleo diet.  Perhaps I’m not as well-read as I thought.  I’ll keep my eyes open for confirmation.

The potential calcium deficiency, I’ve heard of before.  I’m still open-minded on it.  I am starting to wonder if we need as much dietary calcium as the experts tell us.  The main question is whether inadequate calcium intake causes osteoporosis, the bone-thinning condition linked to broken hips and wrists in old ladies.  This is a major problem for Western societies.  Nature hasn’t exerted much selection pressure against osteoporosis because we don’t see most of the fractures until after age 70.  I wouldn’t be surprised if we eventually find that life-long exercise and adequate vitamin D levels are much more important that calcium consumption.

With regards to calcium supplementation, you’ll find several recent scientific references questioning it.  For example, see this, and this, and this, and this, and this.  If you bother to click through and read the articles, you may well conclude there’s no good evidence for calcium supplementation for the general population.  If you’re not going to supplement, would high intake from foods be even more important?  Maybe so, maybe not.  I’m don’t know.

If you check, most of the professional osteoporosis organizations are going to recommend calcium supplements for postmenopausal women, unless dietary calcium intake is fairly high.

If I were a women wanting to avoid osteoporosis, I’d do regular life-long exercise that stressed my bones (weight-bearing and resistance training) and be sure I had adequate vitamin D levels.  And men, you’re not immune to osteoporosis, just less likely to suffer from it.

Insulin Resistance

Insulin resistance from a relatively high-fat diet is theoretically possible.  In reality, it’s not common.  I’ve read plenty of low-carb high-fat diet research reports in people with type 2 diabetes.  Insulin levels and blood glucose levels go down, on average.  That’s not what you’d see with new insulin resistance.  One caveat, however, is that these are nearly all short-term studies, 6-12 weeks long.

If you have diabetes and develop insulin resistance on a high-fat diet, you will see higher blood sugar levels and the need for higher insulin drug doses.  Watch for that if you try the paleo diet.

Are High Total and Saturated Fat Bad?

Regarding relatively high consumption of total and saturated fat as a cause of heart or other vascular disease: I don’t believe that any more.  Click to see why.  If you worry about that issue, choose meats that are leaner (lower in fat) and eat smaller portions.  You could also look at your protein foods—beef, chicken, fish, eggs, offal, etc.—and choose items lower in total and saturated fat.  Consult a dietitian or online resource.  Protein deficiency is rarely, if ever, a problem on paleo diets.

In Conclusion

I think the paleo diet has more healthful potential than realized by the Joslin blogger(s).  I’m sure they’d agree we need more clinical studies of it, involving both type 1 and 2 diabetics.  I appreciate the “heads up” regarding potential vitamin B deficiencies.  My sense is that the Joslin folks are willing to reassess their position based on scientific studies.

I bet some of our paleo-friendly registered dietitians have addressed the potential adverse health issues of the paleo diet.  Try Amy KubalFranziska Spritzler (more low-carb than paleo) or Aglaée Jacob.  I assume the leading paleo diet book authors have done it also.

If you’re worried about adverse blood lipid changes on the paleo diet, get them tested before you start, then after two months of dieting.

Steve Parker, M.D.

PS: The paleo diet is also referred to as the Stone Age diet, caveman diet, Paleolithic diet, hunter-gatherer diet, and ancestral diet.

QOTD: Calcium and the Paleo Diet

“Low calcium intake, which is often considered as a potential disadvantage of the Paleolithic diet model, should be weighed against the low content of phytates and the low content of sodium chloride, as well as the high amount of net base yielding vegetables and fruits.”

L.M. Kowalski and J. Bujko

Hamburger-Avocado Salad with tomatoes, cucumbers, lettuce, salt/pepper, and olive oil vinaigrette

Hamburger-Avocado Salad with tomatoes, cucumbers, lettuce, salt/pepper, and olive oil vinaigrette

PS: Low calcium consumption is thought to predispose to osteoporosis, a bone-thinning disease that causes fractures.  It affects women far more than men.  If you don’t live past 50 or 60, it’s not much of a problem.  Kowalski and Bujko imply that low phytate and sodium content, plus alkaline veggies and fruit, counteract any adverse bone effects of low calcium consumption.  I’m not sure because I don’t read Polish.  Loren Cordain’s paleo diet website talks about the diet being healthy for bones, citing the acid-base issue.

h/t Amy Kubal (Twitter: @AmykRd)

Does the Paleo Diet Cause Kidney Stones?

MedPage Today in May, 2012, reported a substantial increase (70%) in the prevalence of kidney stones in the U.S. over the last two decades. Stone prevalence rose from 5.2% to 8.8% of the population.  Prevalence was based on the periodic National Health and Nutrition Examination Survey, which asked participants, “Have you ever had kidney stones?”

Starting a hundred-yard DASH

Stone prevalence began rising even earlier.  Again according to the third NHANES, prevalence increased from 3.8 percent in the period 1976 to 1980 to 5.2 percent in the years 1988 to 1994.

Older studies estimated that one in 10 men and one of every 20 women will have at least one painful stone by the age of 70.

What are kidney stones make of?  

Three out of four patients with kidney stones form calcium stones, most of which are composed primarily of calcium oxalate or, less often, calcium phosphate.  Pure uric acid stones are less than 10 percent of all stones.

Why the increased stone prevalence?  Does diet count?

Unfortunately, the article doesn’t offer any reasons or even speculation as to why kidney stones are more prevalent.  Kidney stones have a genetic component, but our genes have changed very little over just two decades.  I have to wonder if diet plays a role.

UpToDate.com reviewed diet as a risk factor for kidney stones.  Some quotes:

There are several dietary factors that may play an important role in many patients: fluid, calcium, oxalate, potassium, sodium, animal protein, phytate, sucrose, fructose, and vitamin C intake. Lower intake of fluid, calcium, potassium, and phytate and higher intake of sodium, animal protein, sucrose, fructose, and vitamin C are associated with an increased risk for calcium stone formation. The type of beverage may also influence the risk. The effect of calcium intake is paradoxical, with a decreased risk with increased dietary calcium and an increased or no change in risk with calcium supplements.

The combination of dietary factors may also have a significant impact upon stone risk. As an example, the Dietary Approaches to Stop Hypertension (DASH) diet is high in fruits and vegetables, moderate in low-fat dairy products, and low in animal protein. Based upon an analysis of three large cohorts, adherence to a DASH-style diet lowered the risk for kidney stones among men, older women, younger women, high body mass index (BMI) individuals, and low BMI individuals. Thus, the DASH diet is a reasonable option in the attempt to reduce the risk of stone recurrence.

Higher sucrose [table sugar] intake is associated with an increased risk of stone formation in younger and older women.
The statements above link both low sucrose and high sucrose consumption to kidney stones, so I’m going to ignore sucrose.  The paleo diet, of course, does’t supply much sucrose.
I thought I read somewhere that the paleo diet is potentially deficient in calcium, but I can’t find the reference.  Dr. Cordain at his website suggests that the formal recommended dietary allowance is set too high in any case.  If the diet’s low in calcium, it could predispose to stones. On the other hand, most paleo diet versions are low in sodium and rich in potassium, which may protect against stones.
In Cordain’s 2002 Paleo Diet book, he writes:
In virtually every dietary permutation [of the paleo diet] the levels of vitamins and minerals exceed governmental recommended RDAs.
So does the paleo diet cause kidney stones?  Sorry, but I don’t know.  I tend to doubt it.  I’m not aware of any scientific studies comparing the prevalence of kidney stones in those eating paleo-style with an otherwise similar population.
What about stone prevalence in modern hunter-gatherer cultures?  I bet those data exist, but searching “urolithiasis AND hunter-gatherer” got me nothing at PubMed.  Comparing those cultures with modern Western ones is probably a fool’s errand anyway: too many other uncontrolled variables besides diet.
Standard advice to prevent initial and recurrent kidney stones is to avoid low urine output.  Do that by drinking plenty of fluid.
Although I pay $400 a year for access to UpToDate, they offer free public access to some of the website.  Here’s the UpToDate poop sheet on kidney stones.
Extra credit:  Medical conditions that predispose to kidney stones include primary hyperparathyroidism, obesity, gout, diabetes, and medullary sponge kidney.
For SEO: The paleo diet is also called Stone Age, Old Stone Age, Paleolithic, caveman, and hunter-gatherer, and ancestral diet.