Blood Sugar…shrinks the brain?

Check out this week old study! Subjects had their brain volume examined through MRI four years ago to evaluate changes that may occur prospectively.

“The aim of this study was…to investigate in cognitively healthy individuals, who did not have T2D, whether higher fasting plasma glucose levels falling in the normal range as defined by the World Health Organization were associated with declines in hippocampal and amygdalar volumes.”

The results?

Plasma glucose levels were found to be significantly associated with hippocampal and amygdalar atrophy and accounted for 6%–10% in volume change after controlling for age, sex, body mass index, hypertension, alcohol, and smoking.

High plasma glucose levels within the normal range (<6.1 mmol/L) were associated with greater atrophy of structures relevant to aging and neurodegenerative processes, the hippocampus and amygdala. These findings suggest that even in the subclinical range and in the absence of diabetes, monitoring and management of plasma glucose levels could have an impact on cerebral health. If replicated, this finding may contribute to a reevaluation of the concept of normal blood glucose levels and the definition of diabetes

Pretty fascinating stuff. Keep in mind that diabetic/prediabetic/normo ranges for blood glucose are usually changing. They used WHO guidelines in this study but a range of <6.1 nmol/L is usually the beginnings of pre diabetes for many other guidelines.

From the mayo clinic – Fasting blood sugar test. A blood sample will be taken after an overnight fast. A fasting blood sugar level less than 100 mg/dL (5.6 mmol/L) is normal. A fasting blood sugar level from 100 to 125 mg/dL (5.6 to 6.9 mmol/L) is considered prediabetes

However, the study took this into consideration:

…subanalyses using even tighter inclusion criteria for fasting glucose (<5.6 mmol/L) and for BMI (<25 kg/m2) produced essentially identical findings or, in the case of BMI, slightly stronger findings. This result suggests that the effect of plasma glucose on cerebral structural integrity is not restricted to the upper normal range.

Update: Another study this week showing the differences between Teens with Metabolic syndrome and those that don’t in regards to cognitive function. As expected, cognitive scores were lower in the teens with metabolic syndrome.

References:

Higher normal fasting plasma glucose is associated with hippocampal atrophyThe PATH StudyNicolas Cherbuin, PhD, Perminder Sachdev, MD, PhD, FRANZCP and Kaarin J. Anstey, PhD. Neurology September 4, 2012 vol. 79 no. 10 1019-1026

Obesity and Metabolic Syndrome and Functional and Structural Brain Impairments in AdolescencePo Lai Yau, PhDa, Mary Grace Castro, BSa, Adrian Tagania, Wai Hon Tsui, MSa, and Antonio Convit, MD doi: 10.1542/peds.2012-0324

 

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National Cholesterol Awareness Month and Alcohol Policy to Solve Obesity?

Did you know that September is National Cholesterol Awareness Month? Via our US Department of Health and Human Services:

September may be “back to school month”, but it is also Cholesterol Awareness Month. Take a few moments to study up on this important health issue.

Yes sir! They were kind enough to even link a PDF pamphlet that you can give to all your friends and family. It has handy tips like:

Diet. Saturated fat and cholesterol in the food you eat make your blood cholesterol level go up. Saturated fat is the main culprit, but cholesterol in foods also matters. Reducing the amount of saturated fat and cholesterol in your diet helps lower your blood cholesterol levels

Err…wait a minute…story is a little more complex than that man!

Other tips include eating a:

a low- saturated-fat, low-cholesterol eating plan that calls for less than 7 percent of calories from saturated fat and less than 200 mg of dietary cholesterol per day…Foods low in saturated fat include fat-free or 1 percent dairy products, lean meats, fish, skinless poultry, whole grain foods, and fruits and vegetables. Look for soft margarines (liquid or tub vari- eties) that are low in saturated fat and contain little or no trans fat (another type of dietary fat that can raise your cholesterol level). Limit foods high in cholesterol such as liver and other organ meats, egg yolks, and full-fat dairy products.

Looks like it’s the same old story. If you’ve followed this blog or some of the other people in TheFatNurse’s links, you’ll know the story is way more complex and these diet guidelines may not work for everyone. Saturated fat’s relationship with heart disease is definitely debatable and cholesterol absorption from dietary factors may not have a significant effect on serum cholesterol. In addition, cholesterol as a predictive marker may not even be that accurate in predicting risk for certain people. Perhaps a better (and more informative yet light) way is to spread the cholesterol knowledge through TheFatNurse comics!

Another interesting report from last month that TheFatNurse didn’t see until now is from the CDC via RAND regarding the use of alcohol control policies in controlling obesity and it’s related diseases. They are proposing hypothetical solutions in controlling obesity through similar measures taken in regulating alcohol in the states. The report is aware of the potential controversy that such measures would face:

However, alcohol policies, especially those seen to infringe on individual choice (such as restrictions in outlet density) or to negatively affect moderate drinkers who do not cause harms (such as excise taxation) have been controversial. Over time, many of these measures have become widely accepted and do work in curbing problems related to alcohol use.

In otherwords, people will be upset at having their food choices regulated in order to control obesity…but its for their own good and they’ll get use to it! So what are some ideas? Below is a table from the report. The left column is the alcohol related control policy and how it could be translated to an obesity food regulation policy:

Wow…some of this stuff can look pretty extreme. You’ll see that “fat” foods are targeted. Perhaps before making all these regulatory theories one should question whether dietary fat is a cause of obesity in the first place?

Bottomline: It’s national cholesterol awareness month but the Dept of HHS seems to be putting out the same ol same ol on cholesterol and heart disease. Additionally, some reports are discussing potential ways to control obesity through hypothetical regulations derived from alcohol regulation. As seen with the knowledge on cholesterol, without a true consensus on what causes obesity and it’s related diseases, is food regulation really that wise of a choice? Let’s work on getting the message out on dietary fat and cholesterol beyond fat & LDL cholesterol = bad and HDL = good before working on policies that could potentially cause more harm than good.

Interesting New Meta Analyses Out on BP and Low Carb. Response from Egg Study

In case you haven’t heard, last week the Cochrane Hypertension Group released some compelling updates on Blood pressure medications (1). But before we get to that, you may be wondering what the heck the Cochrane Collaborative is. While TheFatNurse can’t comment on all nursing schools, during TheFatNurse’s time as a wee little nursing student, one of the buzzwords was Evidence Based Practice in school. As a result, one of the organizations to help increase the use of evidence based practice is the Cochrane collaboration.

The Cochran Collaboration consists of over 28,000 volunteers in more than 100 countries that saw a need to organize the medical literature in a way that was easy to understand and evaluate. The goal is to allow evidence based practice to make its way into the healthcare setting. They go about doing this through systematic reviews of randomized control trials. So what did they findout about hypertension and blood pressure?

The Cochrane group set out to see what the literature showed about individuals with anti hypertension medications and mild hypertension (systolic of 140-159 or diastolic of 90-99) but no prior related issues involving cardiovascular diseases/events. They wanted to examine Randomized Control Trial studies that had at least 1 year duration. Specifically, the outcomes from the literature they were examining were all hypertension related such as coronary heat disease, stroke, mortality, total cardiovascular events and adverse effects from medications causing withdrawals. So what did they conclude? In the author’s own words:

In this review, existing evidence comparing the health outcomes between treated and untreated individuals are summarized. Available data from the limited number of available trials and participants showed no difference between treated and untreated individuals in heart attack, stroke, and death. About 9% of patients treated with drugs discontinued treatment due to adverse effects. Therefore, the benefits and harms of antihypertensive drug therapy in this population need to be investigated by further research.

Pretty interesting. Another new study out last week was a meta analysis on low carb diets (2). Here were the results:

A total of 23 reports, corresponding to 17 clinical investigations, were identified as meeting the pre-specified criteria. Meta-analysis carried out on data obtained in 1,141 obese patients, showed the LCD to be associated with significant decreases in body weight (−7.04 kg [95% CI −7.20/−6.88]), body mass index (−2.09 kg m−2[95% CI −2.15/−2.04]), abdominal circumference (−5.74 cm [95% CI −6.07/−5.41]), systolic blood pressure (−4.81 mm Hg [95% CI −5.33/−4.29]), diastolic blood pressure (−3.10 mm Hg [95% CI −3.45/−2.74]), plasma triglycerides (−29.71 mg dL−1[95% CI −31.99/−27.44]), fasting plasma glucose (−1.05 mg dL−1[95% CI −1.67/−0.44]), glycated haemoglobin (−0.21% [95% CI −0.24/−0.18]), plasma insulin (−2.24 micro IU mL−1[95% CI −2.65/−1.82]) and plasma C-reactive protein, as well as an increase in high-density lipoprotein cholesterol (1.73 mg dL−1[95%CI 1.44/2.01]). Low-density lipoprotein cholesterol and creatinine did not change significantly

Again, very interesting stuff. Also David Spence, the author behind the egg yolk as deadly as cigarette smoking study (as some in the media dubbed it), responded to Nutritionist Zoe Harcombe’s critique of his study in her blog’s comments. Just scroll down until you find it.  It’s a good debate between Dr. Spence and Zoe Harcombe.

Picture by Coldbourne from ClipArt. Creative Commons Attribution-Share Alike 3.0

TheFatNurse hopes this is where the future of research is heading towards where debate can occur openly and freely for people to observe and put in their analysis. What would make this better is if all studies were open to the public and not just the abstracts. For example, the two studies TheFatNurse mentioned are not accessible with TheFatNurse’s university account which means TheFatNurse and others can only rely on the abstract to see what the study is about. This is a start, but the abstract tells us nothing about the details on how the experiment was setup, potential confounding factors and other information to allow an honest critique. By having open debate, it’ll be much more productive in moving towards the truth and confirming the validity of studies whether they are for or against the existing paradigm of fat.

References:

(1) Pharmacotherapy for mild hypertension

  1. Diana Diao1,*,
  2. James M Wright2,
  3. David K Cundiff3,
  4. Francois Gueyffier4

Editorial Group: Cochrane Hypertension Group

Published Online: 15 AUG 2012

Assessed as up-to-date: 1 OCT 2011

DOI: 10.1002/14651858.CD006742.pub2

(2) Systematic review and meta-analysis of clinical trials of the effects of low carbohydrate diets on cardiovascular risk factors

  1. F. L. Santos1,
  2. S. S. Esteves2,
  3. A. da Costa Pereira3,
  4. W. S. Yancy Jr4,5,
  5. J. P. L. Nunes3,*

Article first published online: 20 AUG 2012

DOI: 10.1111/j.1467-789X.2012.01021.x

Showing HDL The O Face

Actually it’s more like “OMG my chest hurts so bad!” instead of the above clip from Office Space, but…some people do get symptoms of Acute Coronary Syndrome (ACS) from doing “O Face” type “activities.” What is TheFatNurse reffering to? A new study showing some associations between Apolipoprotein O levels and ACS.

Apo O is a novel lipoprotein found in mostly HDL and researchers are still trying to figure out its role in the body. In the meantime, the new study found associations of increased Apo O levels and people with ACS compared to normal subjects. This was found independent of other lipid markers. So what does this mean? It’s too soon to tell, but this study can be useful for generating further hypothesizes. Perhaps it can be a cardiac marker in the future? Apo O will certainly be something interesting to follow as the research on it continues.

Regardless, this was probably the first study TheFatNurse read that made TheFatNurse extremely hungry…I mean look at this sentence!

ApoO was measured by the sandwich dot-blot technique with recombinant apoO as a protein standard.

Yes TheFatNurse knows they are not talking about food but it makes TheFAtNurse think of:

Filtering studies in the media

So you may have heard about the latest study on eggs and heart disease. The one where CNN and NYdailynews write:

Is eating egg yolks as bad as smoking?

CNN

Like Hollandaise sauce? Too bad — for your heart and blood vessels. Yolks are packed with cholesterol, causing blood-vessel-clogging plaque buildup, just like smoking does.

NYdailynews

Ironically, TheFatNurse saw these articles in the morning when TheFatNurse was chowing down on some eggs. What a way to wake up! Sadly, the article is not  free for view and TheFatNurse’s university account doesn’t have a subscription to it! TheFatNurse isn’t going to plop down 31 dollars for this study – after all 31 dollars can get you 240 eggs at Costco! Even more Ironic…240 eggs per year is about how many eggs the people in the highest egg group ate in the study…CONSPIRACY!?

Anyways, the study looked at carotid plaque buildup and divided the subjects into five groups based on how many eggs they ate via food surveys. They then found an association between egg consumption and plaque buildup. Scary? Not eggactly (hehe), because there are problems galore with the study itself and the way the media is interpreting it. Of course anytime the media represents a study this runs through TheFatNurse’s head:

f

In anycase  Zoe Harcombe has already done a pretty good critique of the study (she has the full study) which you can check out. Like any critique, once you look at how a study is setup, designed, calculated, and interpreted it is quite simple to spot things that are fishy.

Seinfeld Falls For The Old Fat Hypothesis

TheFatNurse recently jogged down memory lane in the 90’s with a few episodes of Seinfeld. You can only imagine TheFatNurse’s delight when an episode about low fat yogurt plopped onto the screen – CAPTURES THE PERSPECTIVE OF FAT SO WELL IN THE FATNURSE’S CHILDHOOD!

Photo by Alan Light; CC 2.0

While the belief that fat is evil still persists today, it was much much worse in the 1990s and this seinfeld episode captures it perfectly:

http://yadayadayadaecon.com/clip/46/

The episode shows Seinfeld and Elaine ecstatic about a new yogurt shop serving non fat yogurt. Both characters can’t believe there is no fat and proceed to gobble down cups and cups only to be shocked when they end up packing on the pounds. It’s revealed that the non fat yogurt actually has some fat in it which is what’s causing the weight gain. Mayor Rudy Giuliani even weighs in on the evils of fat in the non fat yogurt.

TheFatNurse is pretty sure the characters were getting fat not from over indulging in just fat, but also sugar. Even if the yogurt was 100% fat free, the characters would still have gained weight from eating so much yogurt with sugar under the belief that its ok because there is no fat. Look at the nonfat yogurt from Costco: 52 grams of sugar!

It’s a sad reminder of how TheFatNurse grew thinking fat consumption worked. This paradigm that eating fat makes one fat and eating sugar is ok was also shared by a lot of TheFatNurse’s friends growing up. In fact, TheFatNurse even remembers having an old friend who use to indulge in sherbert and yogurt while TheFatNurse ate full fat ice cream because TheFatNurse’s friend didn’t want to get fat…well guess what happened to her?

SHE’S DEAD

…dead emotionally to TheFatNurse that is. Cause we had a falling out but otherwise her health is probably ok.

Anyways, on a related note, a new study (observational study) came out from the Journal of American Board of Family Medicine showing the dangers of obesity may be against what society believes using data from 2000-2006. It’s not the obesity that is causing mortality but the diseases that are associated with it like diabetes and hypertension.

Regarding severe obesity, as in the relatively fewer prior studies examining this category separately,1519 this study found it to be associated with significantly increased mortality risk without adjusting for diabetes or hypertension. However, severe obesity was no longer significantly associated with mortality after adjusting for these conditions, something not examined in the prior studies. Considered in the context of prior studies, these findings suggest that the mortality risk of above-normal BMI, at least in the short term, may be lower in the current era than in the past.

…suggest that efforts to reduce mortality among the overweight and obese might be targeted most productively at individuals with coexisting diabetes, hypertension, or both.

Nice that the study reminds readers that generating conclusions from an observational study is not the same as RCTs!

Given the observational nature of the current analyses, these notions represent hypotheses to be tested in randomized controlled trials.


LowCarb/HighFat or Low Fat + medication on blood pressure

One of the things TheFatNurse has noticed about eating a reduced carb and high fat lifestyle is the drop in blood pressure TheFatNurse is experiencing. Seriously, TheFatNurse has gone from an average of 124/75ish  to…110/62…what the hell…time to look into this mofo.

This is an older study in the Arch of Intern Med from 2010 that is pretty interesting (1). It compared a low carb diet to a low fat diet + Orlistat. This drug works by preventing the absorption of fat and therefore reduce calories. Of course if you ain’t absorbing it…it’s gotta come out somewhere right? Thus, one of the potential “treatment effects” is fat oily and foul smelling stools known as steatorrhea.

Yea…TheFatNurse has random thoughts…Deal with it!

The researchers were looking to see what sort of metabolic, body weight and adverse effects these two diets would have in a 48 week period in overweight subjects with some having obesity related problems such as diabetes, lipid issues and hypertension. However, despite the low fat diet having a leg up with medication versus the low fat diet, the researchers still predicted the low carb diet would make participants lose more weight.

One of the things TheFatNurse always checks when experiments are testing low carb diets is what they mean by “low carb.”. Depending on who’s doing the study, low carb can be defined anywhere from 10 to 40 percent of one’s daily caloric intake. Even a 40% carb diet can technically be classified as low carb since the USDA Dietary Guideline For Americans actually recommends upwards of 65% of your daily diet being from carbs. The diets in this study seemed to reflect the more hardcore low carb community diet:

Participants were instructed to restrict carbohydrate intake initially to less than 20 g/d using pocket guides and hand- outs. Participants could eat unlimited meat and eggs, 112 g of hard cheese, 0.48 L of low-carbohydrate vegetables (eg, leafy greens), and 0.24 L of moderate-carbohydrate veg- etables (eg, broccoli, asparagus) daily; calorie intake was not restricted.

And the low-fat diet with orlistat:

Participants were instructed to restrict intake of total fat (<30% of daily energy), saturated fat (<10% of daily energy), cholesterol (<300 mg daily), and calories using pocket guides, hand- outs, and individualized goals.13,14 Recommended calorie in- take was 500 to 1000 kcal below a participant’s calculated weight maintenance intake.15 In addition, a 30-day supply of orlistat (120 mg before meals 3 times a day) was provided monthly.

Notice something? The low-carb diet had no restriction in calories but the low fat diet followed the usual protocol of eating below your maintenance caloric intake (along with the usual less than 10% saturated daily fat and less than 300 mg daily cholesterol. So what were the results?

Despite the different diets, both groups lost similar weight with no statistical differences. Additionally, triglycerides, LDL-C, HDL-C improved in both groups with no statistical differences either (remember tho, the LDL/HDL  cholesterol isn’t the true benchmark, its the particles but no lipoprotein particle testing was done here). Additionally, TheFatNurse thought the Hemoglobin A1c1% change was pretty interesting. A1C1 measures your sugar levels for the past 3 months and in this study the percent of change was -0.30 (CI; -0.52 to -0.09) for the low carb diet compared to the -0.06 (CI; -0.36 to +0.14) for the low fat diet with orlistat. That’s a pretty good change, although it wasn’t statistically significant (P=0.10); This means there’s a 10% probability that the differences were due to chance. Just an interesting observation.

Perhaps the most interesting portion was the Blood pressure readings. The low carb diet won out with a difference of (in mm Hg)  -7.44 (CI;-11.12 to -3.75) systolic and -4.97 (CI;-7.64 to -2.29) diastolic. with P values for both <.001. People eating the low fat diet with Orlistat actually increased their blood pressure on average.

When one thinks about the diet composition of the low carb group with the results its pretty interesting. Remember the instructions, “eat unlimited meat and eggs.” This translated to the low carb group eating not only more calories in general, but almost double the amount of total fat on a daily basis. As for saturated fat? The low carb group ate a little bit more than double the saturated fat on average daily than the low fat group. Cholesterol intake? Well over double on average compared to the low fat group.

Contrast that with what’s in TheFatNurse’s review textbook that TheFatNurse used for the nursing licensure exam on reducing hypertension:

“Consume a diet low in fat, saturated fat, and cholesterol.”

Hmm…quite the opposite results we got in this study? So why is this? Well the lower carbohydrates consumed will effect the body’s insulin levels. insulin has an effect on the kidneys. It causes your kidneys to retain salt and therefore lead to increased blood pressure. Is this new to you? TheFatNurse thinks it might be for a lot of people, but it shouldn’t be considering “the sodium-retaining effects of insulin have been known for a long time [since 1953].” (2)

Bottomline: TheFatNurse is not against low fat per se, just against the stigma that fat has gotten in today’s society. Additionally, please don’t make the mistake of treating this study as a low fat vs low carb high fat diet (LCHF) fight because the inclusion of orlistat makes true comparisons difficult. Not to mention this is just one study. TheFatNurse used this study to show results can run contrary to what is taught about eating fat and changes inside the body.

Other News: Yes TheFatNurse is updating at a snails pace so far lol. Lots of changes going on right now with TheFatNurse, will hopefully start posting more regularly once things settle down

References:

1) William S. Yancy Jr, MD, MHS; Eric C. Westman, MD, MHS; Jennifer R. McDuffie, PhD, RD, MPH; Steven C. Grambow, PhD; Amy S. Jeffreys, MStat; Jamiyla Bolton, MS; Allison Chalecki, RD; Eugene Z. Oddone, MD, MHS (2010). A Randomized Trial of a Low-Carbohydrate Diet vs Orlistat Plus a Low-Fat Diet for Weight Loss. Arch of Intern Med. 170(2) 136-145

2) B. Grunfeld, M. Gimenez, M. Balzaretti, L. Rabinovich, M. Romo,  and R. Simsolo (1995) Insulin Effect on Renal Sodium Reabsorption in Adolescent Offspring of Essential Hypertensive Parents. Hypertension 26  1089-1092.