Archive for March, 2006

The Metabolic Magic of Magnesium

I often write about the nutrient-density of low-carb and controlled-carb diets because the evidence continues to highlight the importance of critical essential nutrients consumed more frequently with these eating patterns. Today, the journal Circulation published a study Magnesium Intake and Incidence of Metabolic Syndrome Among Young Adults, that found “young adults with higher magnesium intake have lower risk of development of metabolic syndrome.”

Personally I don’t necessarily agree with investigating micronutrients in isolation. The vitamins, minerals and trace elements we require for good health work synergistically with each other – so while a chronic deficiency in one micronutrient can wreck havoc on our metabolism, honing in on and focusing on one micronutrient may not do much for us without taking care of the other essentials that come into play when we consume the micronutrient in question.

Put another way – if we’re eating the right foods, we’re probably going to meet our essential requirements without having to worry about any one nutrient in particular. The foods that are most often recommended as part of a balanced low-carb or controlled-carb diet are the very foods that are rich in micronutrients – non-starchy vegetables, nuts, seeds, fish and some dairy.

Some of your best sources for magnesium are also your best sources of other essential nutrients….pretty convenient, huh?

For example, 1-cup of cooked spinach provides 156mg, or 39.1% of the RDA for magnesium (400mg). Spinach also provides more than 10% of the following essential nutrients too: Vitamin K, Vitamin A, Folate, Iron, Vitamin C, Riboflavin (B2), Potassium, Vitamin B6, Copper, Thiamin (B1), Phosphorus and Zinc.

The list of foods that provide 10% of more of our RDA for magnesium highlights how easy it really can be to meet your nutrient requirements for this essential nutrient each day while following a low-carb or controlled-carb diet. In the list below, I’ve provided some examples and also included other nutrients in each food that also exceed 10% of the RDA for the amount noted:

  • Swiss Chard – 1-cup cooked – 150mg magnesium (37.6% of RDA)
    10% or more of RDA for Vitamins K, A, C, E, Potassium, Copper, Iron and Calcium
  • Summer Squash – 1-cup cooked – 43mg magnesium (10%)
    10% or more of RDA for Vitamins C and A, potassium, copper and folate
  • Baked Halibut – 4-ounces cooked – 121.3mg (30%)
    10% or more of RDA for Vitamins B3, B6, and B12 and Selenium, Phosporus and Potassium
  • Baked Salmon – 4-counces cooked – 138.35mg magensium (35%)
    10% or more of RDA for Vitamins D, B3, B12, and B6 and Selenium and Phosphorus
  • Pumpkin Seeds – 1/4 cup – 184.5mg magnesium (46%)
    10% or more of RDA for Phosphorus, Iron, Copper and Zinc
  • Other foods that are rich (greater than 10% of RDA) in magnesium along with other essential nutrients include: Almonds, Cashews, Yellowfin Tuna, Scallops, Sesame Seeds, Sunflower Seeds, Flaxseeds, Avocado, Hazelnuts (filbets), Peanut Butter, Walnuts, and Plain Yogurt.

And they’re all low-carb too!

All too often we hear misinformation about controlled-carb diets – that they are low in essential nutrients or nutrient deficient. Yet, when we look at the very foods encouraged and recommended, we find they’re among the most nutrient dense available and easily integrated into a low or controlled-carb diet.

And, this particular study adds to the evidence from previous studies that found those who consume the most magnesium have lower risks.

From the Nurses’ Health Study, Magnesium intake and risk of type 2 diabetes in men and women, researchers reported “a significant inverse association between magnesium intake and diabetes risk. This study supports the dietary recommendation to increase consumption of major food sources of magnesium.”

From the Iowa Women’s Health Study, Carbohydrates, dietary fiber, and incident type 2 diabetes in older women, researchers found “a protective role for…dietary magnesium in the development of diabetes in older women.”

And from the Women’s Health Initiative, Dietary magnesium intake in relation to plasma insulin levels and risk of type 2 diabetes in women, researchers concluded that “a protective role of higher intake of magnesium in reducing the risk of developing type 2 diabetes, especially in overweight women.”

In my opinion it isn’t just the magnesium that’s working metabolic magic – it’s the combination of essential nutrients that come together in the foods that are rich with magnesium. Foods rich with magnesium are also rich with other essentials – so eat your non-starchy vegetables, nuts, seeds and fish to ensure adequate intake of not only magnesium, but other critical vitamins, minerals and trace elements too!

March 28, 2006 at 4:59 pm 2 comments

Getting the Facts About Protein

With evidence continuing to support the critical importance of protein in our diet, it still amazes me how often the media continues to perpetrate the myth that all protein sources have similar value in our diet. Case in point, the CBS Early Show Health Watch article, Protein: Getting It Right.

The article opens with – “Protein is a critical part of a healthy diet and the right amount helps with everything from higher energy to stronger muscles. The trick is knowing the healthiest sources of protein and the right amounts for your body.”

So far, so good.

To lend credibility the article offers advice from Elisa Zied, a Registered Dietian and spokesperson for the American Dietetics Association. She correctly includes the reasons why we need protein in our diet, “protein provides the building blocks for our bones, muscles, skin, cartilage, and blood, and helps us make enzymes and hormones that keep our bodies functioning. Protein is the most filling or satiating of all the nutrients and can therefore potentially help us curb our calorie intake and help us achieve or maintain a healthier body weight. Protein can also boost energy by stabilizing our blood sugar levels throughout the day.”

Zied’s advice is good until she points to which sources of protein provide the best nutritional bang: Zied recommends about five and a half one-ounce equivalents of meat and beans each day in a 2,000 calorie diet. The following equals a 1-ounce equivalent of meat/beans:

  • 1 ounce of fish, poultry, or beef
  • 1/4 cup beans
  • 1 tablespoon of peanut butter or 1/2 ounce (2 tablespoons) nuts
  • 1 egg

Three cups of beans per week is the recommended amount, and a great option for vegetarians. “These are great sources that give iron, zinc and healthy fiber which can fill you up as well,” said Zied, and also supply folate and antioxidants. She points out, though, that they are very filling and high in calories, so a portion is 1/4 cup.

The quality of protein is measured by its amino acid content. Foods rich with the full spectrum of “essential amino acids” are better than those which have one or more “limiting amino acids” – that is they lack a high enough level of one or more amino acids and therefore require one to eat more or eat another food limited in an amino acid to make up the shortfall. Foods that provide good levels of all the essential amino acids are considered “complete proteins,” whereas foods that have a limiting amino acid are considered “incomplete proteins.”

Foods are rated according to the Protein Digestibility Corrected Amino Acid Score (PDCAAS). This is a method of evaluating the protein quality based on the amino acid requirements of humans. A PDCAAS value of 1 is the highest, and 0 the lowest. Some ratings of commons foods include eggs (1.0), casein (1.0), milk (1.0), whey (1.0), beef (0.92), kidney beans (0.68), lentils (0.52), peanuts (0.52), wheat (0.25).

So, what’s wrong with her list of foods?

The one-ounce equivalents aren’t the same for quality protein content. In fact, they’re not even close due to the limiting amino acids in the beans, peanut butter and nuts, and also the fact that these items provide less protein per ounce than the eggs, fish, poultry or beef.

Since the article is highlighting the importance of protein, let’s take a look at some important differences in each food above and dispel some of the myths put forth.

1. “[P]rotein provides the building blocks for our bones, muscles, skin, cartilage, and blood, and helps us make enzymes and hormones that keep our bodies functioning.”

This is the critical reason we need quality protein in our diet each day. When you choose foods with complete proteins, you have a better chance of meeting your requirements for essential amino acids – and you’ll consume less calories in the process too – than if you choose foods with limiting amino acids.Just how different is the amino acid profile between two foods?

Take a look at the difference between the egg and a tablespoon of peanut butter:

Egg/Peanut Butter

  • Calories: 74/94
  • Phenylalanine 0.339g/0.209g
  • Valine 0.428g/0.169g
  • Tryptophan 0.277g/0.138g
  • Isoleucine 0.335g/0.142g
  • Methionine 0.190g/0.049g
  • Histidine 0.154g/0.102g
  • Arginine 0.409g/0.483g
  • Lysine 0.455g/0.145g
  • Leucine 0.541g/0.262g

Not only does the peanut butter cost you 20-calories more, it’s “limited” because of the low level of methionine, and except for arginine, provides much less of every other animo acid considered “essential” – that is, required by humans. In fact, you’d have to eat almost 4-tablespoons of peanut butter, costing you 364-calories, to overcome the limiting amino acid in peanut butter.

2. “These are great sources that give iron, zinc and healthy fiber which can fill you up as well,” said Zied, and also supply folate and antioxidants. She points out, though, that they are very filling and high in calories, so a portion is 1/4 cup.

The above statement is a bit misleading, and might lead one to think that eggs, beef, poultry or fish do not contain similar nutrients. This time, let’s look at the eggs nutrients and 1/4 cup of pink beans:

Beans/Egg

  • Calories: 63/74
  • Calcium: 22mg/26mg
  • Iron: 0.97mg/0.92mg
  • Zinc: 0.41mg/0.55mg
  • Phosphorus 70mg/95mg
  • Selenium 0.6mg/15.8mg
  • Riboflavin 0.02mg/0.24mg
  • Vitamin B-6 0.07mg/0.07mg
  • Folate 71mg/24mg
  • Vitamin E 0.43mg/0.48mg
  • Vitamin B-12 0.00/0.64mg
  • Vitamin A 0.00/242IU
  • Vitamin D 0.00/17IU

With the exception of folate (which you should be getting plenty of from your vegetables) the egg provides more important nutrients than the 1/4 cup of beans! And, like the peanut butter, the amino acid profile of the beans falls short when compared with an egg. To overcome the limiting amino acid in beans, and consume more nutrients, you’d have to eat more than three 1/4 servings – costing you 211-calories – and you’d still not consume any Vitamin D, A or B-12 and still not consume as much selenium or riboflavin as you would with an egg.

3. Zied recommends about five and a half one-ounce equivalents of meat and beans each day in a 2,000 calorie diet.

This is one recommendation I take issue with repeatedly as it fails to provide adequate intake of complete protein. Because the current dietary recommendations base intake of carbohydrate, protein and fat on percentage of calories this type of simplistic advice is provided again and again without considering the potential danger to the individual following the advice.

Quite frankly, for most men 5.5-ounces of protein-rich foods in a day is simply inadequate, regardless of the source, for overall total protein intake at the end of the day. For a good number of women, it’s also inadequate – especially if one is choosing incomplete protein sources more than complete protein sources, which is currently the recommendation (eat more plant based foods instead of aminal foods).

The Institutes of Medicine (IOM) consider quality protein to be critical and are clear in their recommendations – protein must provide adequate intake of all indispensible amino acids and care must be taken when protein sources are limited in amino acid content. In addition, they set the minimum intake of complete protein at 56g for men and 46g for women. And, let’s be clear – that’s “complete” protein, not “total protein” in a day from all sources. They also carefully calculated amino acid requirements based on quality protein intake for each of the essential amino acids which is based on miligrams (mg) of amino acid required for each gram (g) of protein consumed.

So, just how risky is the advice to consume just 5.5-ounces of meat and beans with the emphasis on the beans?

In a single day eating 3-ounces of cooked beef (ground, lean, broiled), 1/4 cup of pink beans, a tablespoon of peanut butter and 1/2 ounce of almonds would fulfill the recommendation based on “ounce equivalents” but falls short on actual protein consumed – just 30g – and is deficient in essential amino acids, specifically falling short for phenylalanine and methionine. Including the beef simply wouldn’t overcome the limiting amino acids in the other foods. If you followed the advice and consumed no other “protein-rich foods” – that is no more beans or eggs or meats – but relied on other foods like vegetables, fruits, and grains to round out your menu and provide your calories, you’d still fall short for protein and amino acids no matter how many calories you ate.

The bottom line is that when it comes to protein in your diet – quality counts!

Not only will you cosume complete proteins with eggs, meats, poultry, fish, and dairy, you’ll also consume higher amounts of vitamins and minerals critical for good health. These foods are and should be recommended as the “gold standard” for quality protein and should be your first choice for protein!

March 24, 2006 at 6:38 pm 5 comments

Hitting Below the Belt…

Today Dr. Mike Eades brilliantly [that is the only way to describe his article] takes readers through the Lancet publication of A Life Threatening Complication of the Atkins Diet.

The comedy of errors he points out are funny, yet disturbing when you really think about it – had the media paid better attention to the facts, the headlines would have read “Buffoons misdiagnose mild gastroenteritis, costs patient thousands.”

Then again, had the peer reviewers at the Lancet paid attention, the case report never would have been published – but that’s another story!

I hope you enjoy Dr. Eades article, Low-carb diet takes one below the belt.

March 24, 2006 at 4:21 pm Leave a comment

Talk About Creativity!

Usually when researchers find no measurable differences between groups they’re observing, they’ll either choose to tell it like it is and reach the honest conclusion that there was no difference, or they’ll simply not publish their findings.

This month however, it appears researchers got creative to find statistically significant differences in the publication of Weight gain over 5 years in 21,966 meat-eating, fish-eating, vegetarian, and vegan men and women in EPIC-Oxford, published in the International Journal of Obesity.

I say “creative” because the research team abandon the traditional measurements of pounds and/or kilograms and instead reported their findings in grams! Not only did this sleight-of-hand help massage the data to statistically significance, it also got the attention of the media as we see in the Globe and Mail article, Need a carrot to stick to vegetarian eats?

Creative statistics may get you in the media, but it’s intellectually dishonest and purposely misleading. In two words, bad science.

So, what’s the hub-bub about?

The researchers purport to show there is a statistically significant difference between different dietary habits on weight gain over a period of five years. The dietary patterns observed included meat-eaters, fish-eaters, vegetarians and vegans. At the end of the five years, there was no difference between the groups. This is stated, very clearly, in the abstract: The differences between meat-eaters, fish-eaters, vegetarians and vegans in age-adjusted mean BMI at follow-up were similar to those seen at baseline.

But then we find creativity at work with the data – after massaging the data to death, it’s finally found that vegans gained less weight annually than fish-eaters; who in turn gained less weight than meat eaters. The conclusion – During 5 years follow-up, the mean annual weight gain in a health-conscious cohort in the UK was approximately 400g. Small differences in weight gain were observed between meat-eaters, fish-eaters, vegetarians and vegans. Lowest weight gain was seen among those who, during follow-up, had changed to a diet containing fewer animal food.

How much weight are we talking here? Oh, an ounce or so. So completely insignificant and totally able to be skewed by something as benign as a participant drinking a glass of water before they weighed.

But, convert the ounces to grams and, viola!, you have differences that suddenly reach statistical significance deemed worthy of publication, press releases and media attention!

What we really have here is data that’s completely worthless – it offers us nothing more than a lesson in data massage and creative presentation. At the end of five years there was no statistical difference between the groups in pounds or kilograms, and there certainly was no clinical significance to support the media attention or recommendations making the rounds to eat less animal foods.

March 23, 2006 at 7:00 pm 1 comment

Metabolic Syndrome – Which Came First, the Chicken or the Egg?

At the annual meeting of the American College of Cardiology earlier this month, some startling figures were presented – there’s an alarming rise in the number of people with the constellation of heart-disease risk factors known as the metabolic syndrome: the presence of at least three of the following risk factors: obesity, high blood pressure, high triglycerides, low HDL cholesterol, or high fasting blood sugar.

Additionally some clinicians also consider high LDL, high insulin, and waist-hip ratio or abdominal adiposity as risk factors. Some are also measuring inflammatory markers like C-Reative Protein (CRP).

The incidence of metabolic syndrome hasn’t just increased – it is skyrocketing. As reported on WebMD – Metabolic Syndrome Skyrocketing – Despite the improvements seen in some heart disease risk factors, a survey of nearly 80,000 people showed that rates of the metabolic syndrome continued to rise both in the United States and in Europe.

The surge is driven mainly by the epidemic of obesity in the Western world, says researcher Benjamin A. Steinberg, a Sarnoff fellow at Brigham and Women’s Hospital in Boston.

We’re not doing much better with cardiovascular disease either. The survey estimates that in 1998, 61.4 million American adults were estimated to have cardiovascular disease or risk factors for coronary heart disease. That figure rose to 66.7 million in 2001 and to 67.2 million in 2004.

This is in light of the improvements seen with cholesterol levels across the board!

During the six-year period, some major gains were made in reducing the number of people with heart disease risk factors.

For example:

  • The percentage of people with high triglyceride levels dropped from 46% to 40%.
  • The number of people with low HDL cholesterol levels decreased from 35% to 33%.
  • During this time frame the use of cholesterol-lowering statin drugs increased from 37% to 52%.

Yet despite these improvements, the rates of the metabolic syndrome rose from 36% to 44% during the same period.

So, what do the “experts” tell us is driving the alarming rate of metabolic syndrome?

Obesity.

That means the rise [in the metabolic syndrome] is primarily driven by the skyrocketing rates of obesity — from 30% to 48% — during the six-year period, says America Heart Association president Robert Eckel, MD, professor of medicine at the University of Colorado Health Sciences Center in Denver.

“Although several components of the metabolic syndrome are better off, people are still much more likely to be obese,” he tells WebMD. “We have to continue to target obesity to reverse these trends.”

Yes, I’m shaking my head here, wondering if they’ll ever “get it.”

Metabolic syndrome is one of those “chicken and egg” disorders – which came first, the metabolic dysfunction or the obesity, dyslipidemia, hypertension, insulin resistance, or high fasting blood sugars? The American Heart Association (AHA) apparently believes it is the obesity driving the disorder. Their recommendation – a low-fat diet to reduce weight coupled with increased physicial activity.

The problem with that recommendation? Data from numerous trials shows that a low-fat carbohydrate rich dietary pattern actually worsens the other risk factors for metabolic syndrome with increased triglycerides, decreased HDL. Without significant weight loss, such a diet may also increase insulin resistance and worsen fasting blood sugars due to the high carbohydrate intake required to achieve a fat intake less than 30% of total calories.

The AHA is fully aware of this, yet continues to ignore the data that clearly points to a low-carb diet as a better approach to tackle ALL the risk factors with dietary modification. The Nutrition & Metabolism Journal recently published the review, Carbohydrate restriction improves the features of Metabolic Syndrome. Metabolic Syndrome may be defined by the response to carbohydrate restriction, that included 112 references.

The bottom line? The review summary stated: Five symptoms common to most definitions of MetS are those that are reliably improved by CHO restriction. Carbohydrate restriction is one strategy for weight loss but, in addition, improves glycemic control, insulin levels, TAG and HDL levels even in the absence of weight loss. We suggest that response to CHO restriction may, in fact, be an operational definition of MetS. Its underlying basis would rest on the idea that the features of MetS are associated with a disruption in insulin metabolism which is strongly influenced by dietary CHO. The extent to which this definition is useful may depend on its application by individual practitioners. Experimental studies that follow its lead or conversely disprove its fundamental premise should advance our understanding of obesity, diabetes and CVD. Dismissing CHO restriction without evidence, or expressing “concerns” rather than offering data will probably be less productive.

Folks, obesity is indeed contributing to the increase in metabolic syndrome. However, the answer to reverse the trend is not as simple as losing weight. The only way to reverse the trend is to identify the driving factor behind our obesity AND metabolic dysfunction issues – resolve the underlying reason for our weight gain and identify what is disrupting our metabolic pathways so negatively.

The AHA takes the simplistic approach – eat less and exercise more – as the solution.

I’d like to know just how many people haven’t already heard that advice and tried it only to fail again and again as their metabolic dysfunction worsens and their risk factors increase?

Until we move past the deeply rooted dogma that preaches the carbohydrate rich low-fat diet as the end-all-be-all and actually move instead toward an evidence-based approach, we’re going to continue to see the alarming rate of metabolic syndrome rise higher and higher.

You don’t have to wait for the “experts” to finally “get it” – your long-term health depends on educating yourself about what the science says, what the research data shows us and making an informed decision about taking control of your diet to improve your risk factors. A controlled-carb approach offers improvements in weight, HDL cholesterol, blood pressure, triglycerides, insulin senstivity and glycemic control.

If you’re waiting for the leading organizations to suddenly accept and take the evidence-based approach any time soon and give you a greenlight to follow a controlled-carb diet – well, let’s just say you might not want to hold your breath. There is way too much invested in the dogma and things will not change until the perspective is changed to focus on public health instead of the bottom-line dependent on the status quo.

March 21, 2006 at 3:20 pm Leave a comment

Cholesterol & Food

On March 9, 2006 I wrote about the findings from a study using a “portfolio” of foods in an attempt to use a low-fat diet to lower cholesterol. Today, the Washington Post carried Sally Squires take on that study in the Lean Plate Club – Portfolio Diet: Tough to Stay Invested In.

As is often the case, I have to wonder if Ms. Squires read the full-text of the study or not. More troubling is her recommendations to swap the foods that were part of the study for other foods, even though those foods were not part of the trial!

My article on the study is here: This is Success?

I’ll add today, that the results were not impressive when you consider that 70% of those who followed the diet enthusiatically did not see a benefit. In reviewing various dietary interventions, a low carbohydrate diet has a much more dramatic effect on cholesterol levels and ratios in a much shorter period of time. Diet can indeed be used to effectively improve cholesterol – a low-fat diet is not the best option however.

March 21, 2006 at 1:42 pm Leave a comment

Ketoacidosis – A Complication of Atkins’ Diet?

Today’s headline in Bloomberg caught my attention – Low-Carb Atkins Diet Isn’t Safe for Losing Weight, Doctors Say – sounds like the same old, same old warning, huh?

The opening sentence is certainly alarming: The low-carbohydrate Atkins diet, which experienced a peak of popularity two years ago, isn’t safe and shouldn’t be recommended for weight loss, according to doctors writing in The Lancet.

And once you get past the first few paragraphs you find the cause for this ‘sounding the alarm bells’ – In a case report, doctors including Klaus-Dieter Lessnau, clinical professor of medicine at New York University School of Medicine, described a 40-year-old white female patient from February 2004 who was vomiting as often as six times daily and had difficulty breathing after strictly following the Atkins diet for a month. She reported a weight loss of 9 kilograms (20 pounds) while on the diet.

I really had to go read the case study for myself since the media reports, found in literally hundreds of sources today – from the Chicago Sun Times to Forbes, from ABC Online to USA Today – are carrying the story with scant details.

The details from the media include: the woman was 40-years old, obese, vomiting six times a day, and the Atkins Diet caused her to develop ketoacidosis.

The case study was published in the Lancet. Fortunately for all the alarmists, it’s within the confine of “premium content” so it’s not publically accessible without paying to read it. I’ll just say here that limited access must go by the way-side if we’re going to advance evidence-based medicine…full open-access is the way to do this, but that’s an entirely different subject!

So, what did the case study tell us that the media isn’t? More importantly, does the information contained within justify the frenzy of alarm today?

Let’s tackle the first question first. Within the case report are the following details: the woman was 40-years old, obese with a BMI of 41.6, who’d followed the 1972 version of the Atkins diet for one-month before she lost her appetite and started to feel nausea. During that time before she started feeling ill, she was eating meat, cheese and salads daily, was taking an assortment of nutritional supplements and lost about 20-pounds in the month. Five days prior to her emergency room visit for shortness of breath, she’d vomited four to six times a day.

The report notes that other than the mild distress, clinical examination was “unremarkable” with normal vital signs. Blood tests showed a high level of lipase (indicative of pancreatitis) with normal amalyse, which confuses things since both are elevated with pancreatitis – sometimes this type of reading is actually suggestive of something more sinister happening, specifically cancer. But we find no mention of that possibility in the case report.

The report does state, clearly, that a CT scan of her pancreas on admission was normal. Interesting, at least to me, is that with ketoacidosis her glucose would be high (at a level greater than 14mmol/l – hers was 4.2mmol/l) and her sodium would be abnormal, yet it was normal according to the report. But, hey, what do I know?

The diagnosis of ketoacidosis in this woman was based on “The differential diagnosis of high-anion-gap metabolic acidosis includes ingestion of methanol, ethylene glycol, or salicylate, L- or D-lactate acidosis, and ketoacidosis due to diabetes mellitus, alcohol, or starvation.” It’s clearly stated that “Our patient denied alcohol use; her serum osmolar gap was 0, which excludes the presence of unmeasured osmotic agents such as methanol or ethylene glycol; L-lactate concentration was normal; and salicylate was undetectable. D-lactate acidosis was unlikely without antibiotic use or bowel surgery. Serum was positive for acetone, and ß-hydroxybutyrate was high at 390 µg/mL (normal 0–44 µg/mL), consistent with ketoacidosis.”

Quite frankly, the level of ketones in her urine are not alarming for someone who is not diabetic or someone properly following a low-carb diet…but let’s keep moving forward and get through this report. The author states that in trials where children are fed a ketogenic diet for epilepsy ketoacidosis is a complication.

Unfortunately, the reference he cites as his evidence, did not have ketoacidosis due to diet as a complication. Nice try though – Fanconi’s renal tubular acidosis, reported as a complication in one patient in his citation, is a disorder that may be inherited as a primary disorder or may be one symptom of a disease that affects many parts of the body. Researchers have now discovered the abnormal gene responsible for the inherited form. More often, however, classic distal renal tubular acidosis is a complication of diseases that affect many organ systems (systemic diseases), like the autoimmune disorders Sjögren’s syndrome and lupus.

Gotta give him credit for trying! I check referenced citations specifically because I see, too often, a study referenced and when you read through the data, the data doesn’t support the use of the citation in context to support an assertion.

Here’s the main problems with the case report.

The symptoms of acute methanol poisoning are shortness of breath, vomiting, headache, with metabolic acidosis occuring often. The course of treatment for her was dextrose and sodium bicarbonate infusion – the course of treatement for methanol poisoning.

She’d been vomiting for days – that alone will upset her electrolyte levels and cause dehydration. Five days of vomiting – well, you can imagine just what state her body was in by that time. The vomiting and dehydration are glossed over as inconsequential to make the case it was the diet – and only the diet.

So what’s that now? Two possibilities besides the diet?

How about another – maybe she did drink alcohol and that disturbed her metabolism leading to the acidosis state. Yes, alcohol can do this to a person, regardless of the diet they consume!

Lastly, she may have actually had undiagnoised diabetes and/or a cancerous tumor that would have also served as the catalyst for her symptoms.

We just don’t know since none of the other possibilities were explored – the diet was the cause in the mind of her physician, so there was no further investigation.

That troubles me – we have thousands of participants from hundreds of studies to date and not one incident of ketoacidosis. Is it possible this woman’s ketoacidosis was a result of her diet? I would say it’s not impossible, but very highly improbable given the reams of data from clinical trials to date that have not found ketoacidosis as a complication, even in diabetic patients following a low-carb diet.

The reason it isn’t a complication is that dietary ketosis, in and of itself, does not cause ketoacidosis. More likely this woman experienced ketoacidosis as a result of something else and unfortunately her diet placed an obstacle in front of a complete investigation as to its cause.

That said, I cannot state strongly enough that one person is not evidence to indict a low-carb diet as dangerous. Which leads to my answering the second question above – does the information contained within justify the frenzy of alarm today?

We do not see this frenzied alarm when someone in a statin trial experiences complications which may or may not be related to the drug nor do we see such alarm when someone participating in a low-fat diet trial experiences a complication which may or may not be due to their diet.

In the real world, one person in a case study presenting information about one person is considered to be the “n of 1” – meaning there is no other person to compare them to – their symptoms and course of treatment are in isolation to a greater population and highly dependent on the investigation, or lack thereof, of causes related to the symptoms.

While this particular case study was interesting, it remains an “n of 1” since there are no other reports of this type of complication from any other clinician in the world, and the physician did not, in my opinion, explore all avenues for cause since he believed it could only be her diet – short-sighted and a headline grabber to be sure.

Good science? No.

Correction: In the originial publication of this article I noted the woman’s blood pH was normal. In reviewing the case report again, I realize I read through the details too quickly and was incorrect – her pH was lower than normal, suggestive of acidosis. The sentence was edited out for accuracy.

March 17, 2006 at 6:18 pm 3 comments

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