Showing posts with label Health. Show all posts
Showing posts with label Health. Show all posts

Friday, October 11, 2013

What is the Real Deal behind Preventing Cardiac Risk?


It's been quite a while since my last post.  I am neck deep in preparing for my PhD Comprehensive exam (early Dec 2013), working full time & caring for my almost 2 year old daughter as my wife and I have another child on the way (due Feb 2014).

I have to tell you honestly, that I am constantly disappointed by the current medical profession specifically when it comes to dealing with chronic diseases! As a registered dietitian I see it as my duty to constantly review the literature to see what new innovations might show promise. It's my responsibility to understand these novel studies so that when clients inevitably ask about them, I will be able to give them legit advice & not just tow some antiquated party line!

Okay, enough venting!  Let's dive into some of the newer evidence on Heart Disease Risk!


The Popular Dogma is Not Supported by Current Evidence

1)      Saturated Fat
a.       The current dogma is that eating too many saturated fats increases blood cholesterol, which in turn increases risk for heart disease.

b.      A few studies have shown that there increased levels of LDL increase risk for CHD.

c.       But, recent research concluded that there was in fact no association between dietary cholesterol and CHD.

d.      As of 1977 AMA/CMA recommended lowering fat intake to 30% or less in diet – result=significant change in diet composition - ­ Carb/­ PUFA (specifically vegetable oils – all ­ omega 6).

e.      If we oversimplify and just ask two basic questions, we start to see the challenges that have arisen: i) What about evolution? Did we evolve eating more carbs and seeds & nuts or animal & coconut fats? ii) What about inflammation? Which is more inflammatory in nature: SFA or omega 6 + refined carbs?

2)      Apo lipoprotein Changes
a.       This change in diet comp – resulted in changes to our circulating lipoproteins that actually increase our risk for CHD (specifically - ­ Triglycerides/ ¯ HDL particles).

b.      New technology explains why LDL amount is not as telling as once believed.  Particle size of   Think of cholesterol as the passengers in a car and the particle number is the number of cars on the road.  If there are more particles around then they are more likely to crash into the arterial linings and become trapped (atherosclerosis).  If LDL particles are smaller, there will be more of them present, when they are fluffy and big, and then there will be less of them.  Theoretically, the amount of LDL could be the same in both scenarios, but it’s the small, dense LDL particles (that are more abundant) that increase the risk for CHD.
LDL particle size is far more predictive of atherogenic risk.

3)      The Role of Carbohydrates in CHD
a.       Carbohydrates were pre-farming available in unrefined forms (vegetables & fruits) and only in the late summer and fall.  Today, we have year round access to the most highly refined carbohydrate sources we’ve ever seen.

b.      High carbohydrate intake shuts down fat burning & promotes fat storage.  This increased fat storage leads to an increased production of triglycerides.
c.       Hypertriglyceridemia is accentuated in people with abdominal obesity/insulin resistance.

d.      This insulin resistance occurs in the face of high carbohydrate diets & is now considered a protective measure by the liver to prevent substrate overload.

4)      The Role of Inflammation
a.       Athersclerosis does not occur in a vacuum (so to speak).  Inflammation and oxidation are required to promote infiltration of lipids within the arterial walls and the binding of minerals to them (plaque formation).

b.      High carbohydrate diets & especially refined carbohydrates are highly pro-inflammatory.

c.       Omega 6 fats are essential (small amounts) but in excess are highly pro-inflammatory.  They are highly available in Western diets (corn, soy & wheat oils) as well as most nuts & seeds.

d.      Recent studies have shown that low carbohydrate diets are effective at reducing cardiovascular risk factors.
Citations:
Djousse, L and Gaziano, JM, 2009.
German, JB and Dillard, CJ, 2004.
Agius, L, 2013.

Monday, July 8, 2013

Are Low Carb Diets the Devil?


Hi everyone,

A quick disclaimer to go with my post.  I hope you find the information useful!
 
Remember, I do not know your case at all.  Be sure to discuss this with your doctor or a health care provider who does know your case well, before attempting.  I am providing you with information to better understand a nutrition protocol and how it might be useful to you, but am in no way suggesting you do it.  As such, I am not responsible if you do try this unsupervised and bugger yourself up.  Use your common sense, and discuss this with someone who can help you do it safely.

As a registered dietitian, we are often taught that Atkins was a loon & that low carb diets are the bane of health & longevity. Well, after delving into the research & examining this topic for myself, and also experimenting with this practice personally (n=1 experiment) I can say, that they are definitely NOT the devil & they might actually possess some incredible therapeutic benefit!  Read below & draw your own conclusions.


What is Ketosis
State of elevated levels of ketone bodies throughout the body (including the blood).  These are formed by ketogenesis when liver glycogen stores are depleted. Two major ketone bodies used for energy are acetoacetate and β-hydroxybutyrate.  Both are readily used by most of the tissues of the body except the heart & one portion of the brain.  Interestingly, humans have evolved a method of creating glucose from broken down proteins (certain amino acids).  While semantic debate rages on about why we evolved this capability, the fact is we have it and as a result, we really don't need much direct carbohydrate intake to live healthfully!  The only caveat I will add now is that if you have to perform physically demanding and performance dependent activities on a regular basis, then you will need to add more carbohydrates (complex, safe starches are excellent for this) in the 3-4 hours post activity.

Common Concerns:

As a health professional, the most common concerns that I've read about, heard or even stated as fact myself (incorrectly, I might add) are here:

1)      Ketosis is harmful – The fact is if glucose cannot be broken down (i.e. insufficient insulin levels) then the body metabolizes fat, which will increase blood ketone levels leading to ketosis.  The ketoacidosis situation arises when these ketone bodies continue to elevate due to the complete lack of insulin and the fact that sugar is being consumed and remaining unused in the blood stream.  This leads to high levels of ketone bodies and high levels of blood glucose concomitantly, which decreases the pH of the blood (increases acidity) leading to metabolic acidosis in which enzymes, tissues and organs can fail leading to coma and subsequently death.  Obviously, that is something that we would all like to avoid like.  However, it’s critical we understand that an otherwise healthy person who is making insulin readily can undertake a well-designed low carbohydrate diet safely.  They will be in ketosis, which can be extremely beneficial.

2)      High Protein diets and kidney failure – it’s believed that higher protein consumption increases risk of kidney damage.  This has been disproven by several well-designed long term studies. The only caution I would mention is that people suffering from failing kidney function already or those at high risk for kidney failure (i.e. long term poorly controlled diabetes) or gout might require limited protein intakes.  Otherwise, there is no known upper safe limit for protein intake.

3)      Cognitive burnout - My Brain & nerves needs sugar as a fuel – This is true, to an extent. Parts of the brain can burn only sugar as fuel, however, the body can create sugar via gluconeogenesis (in the liver) from proteins, which is one of the reasons why protein intakes are elevated in low carbohydrate diets.  Furthermore, the only studies that I've seen linking low carb intake to poor cognitive performance vs. high carb intake were in subjects that were NOT fat-adapted.  In other words they did not undergo the 2-4 week adaptation/detox phase in which their body decreases carb burning pathways & upregulated fat burning ones, making us efficient at fat burning.  Anyone, detoxing would not perform well on cognitive test.

4)      High fat diets and high cholesterol – It’s still (erroneously) believed that a high fat diet leads to cholesterol elevation.  This has been disproven by several well-designed studies and it has been established that refined dietary carbohydrate is far more likely to lead to metabolic syndrome and dysregulations in cholesterol that significantly increase risk for heart attack or stroke.  Furthermore, overt blood cholesterol values are less meaningful than once believed.  More telling tests including LDL-particle size, which unfortunately is not routinely available, is one of the best to determine cardiovascular risk vs. LDL number.

5)    Low carb diets will increase risk for Cancers due to low fruit & vegetable intake – It’s (erroneously) believed that high animal protein, high fat diets increase risk for cancer.  There are two active hypotheses.  The first is that animal protein causes cancer.  This comes from studies that showed an association between animal protein intake and cancers, however, on further examination, the data analysis is suspect. For example, whenever pizza (with peperoni) was consumed all the calories were counted as animal protein and including lunch and cured meats as animal protein sources would definitely skewed results, especially in light of the huge body of evidence linking sodium nitrates and the like to stomach & bowel cancers (strongly).  The second hypothesis implicates lack of vegetable matter in this; however, it is carbohydrates that are being restricted, not vegetable matter.  Whenever I am counseling someone on a ketogenic protocol, I recommend that people consume low carb vegetables with every meal and use fruit sparingly.  In the end, clients consuming a low carb paleo diet often consume more plant matter compared with the usual North American diet.  In fact, dietary carbohydrate especially from refined grains, sugars, etc... and excess fat mass have been implicated in causation of many cancers.  Even more research, has demonstrated a treatment enhancing effect by using a ketogenic diet.  Specifically, the theory is that a tumor uses glucose as its primary fuel source, and is unable to utilize ketone bodies, whereas humans can adapt to ketone bodies.  There are many studies showing that a ketogenic diet during cancer treatment helps to eliminate tumors faster and more effectively than traditional treatments alone, likely because it starves the tumor.  Specifically, most of the research on ketogenic diets improving cancer outcomes have examined endothelial derived cancers (i.e. bowel and breast, etc...).

What are the Benefits of a Low Carbohydrate diet?
1)      Decreased hunger - more insulin stability and presence of ketone bodies both act to increase satiety.
2)      Long-duration fuel supply - decreased dependency on quick burning sugars allows for longer lasting, more stable energy levels.
3)      Decreased exposure to highly toxic refined grains & other processed foods - the processing used in preparations of grain products, juices & sugars, etc... act to increase our exposure to many chemicals the effects of which in the long term are unknown.
4)      Reduction of over-stimulation to the brain (i.e. with seizure disorders, depression, bipolar disorder and schizophrenia) - this has been examined for years in children with epilepsy, but more recent studies have found success in subjects with other brain disorders. This is likely due to reduction of readily available, fast burning sugar, so the brain is better able to regulate the use of energy even in hyperactive firing areas.

Okay, I would like to give this a try, how the hell do I do it?

How do I achieve Ketosis?
In order to enter into ketosis, the average person needs to consume < 100 g of total carbohydrates per day.  Metabolic individuality might mean that some will enter ketosis slightly above or below that, but that seems to be a reasonable goal amount for carb intake to be below for ketosis.  This is carbohydrates from all sources, but I strongly suggest eliminating highly refined carbohydrates (I.e. sugars) and grain products (especially wheat), and possibly even dairy for at least 60 days to see how you look, feel and perform (depending on your specific individual goal) and then reintroduce as tolerated, if desired.  This could provide many further benefits in addition to ketosis.  This means that your only sources of carbohdyrates for those 60 days will be low carb vegetables, starchy vegetables and limited whole fruits.  Many of you might recognize this as a low carb paleo diet.

Why is Ketosis safe for most of us?
Human evolved over millions of years before agriculture (only about 10,000 years old) with a cyclical pattern of eating, often famines followed by feasts, etc… Furthermore, there was only a brief time relative to today that fruits & vegetables would have been plentiful (i.e. late spring/summer & fall).  This means that over-winter and even into spring there would have been limited amounts of carbohydrates available at all.  We had to adapt to a long lasting fuel source to allow us to survive over winter.  This is likely why fat evolved and metabolically why we can adapt to ketone bodies as a fuel.
Interestingly, even today there are many documented cases of human societies today that exist in a long-term ketogenic state. After a 2 to 4 week period of adaptation, human physical endurance is not affected by ketosis, according to studies - meaning that we do not necessarily need a high carbohydrate intake in order to replace depleted glycogen stores for exercise. This makes the argument more compelling that; in fact, we are designed to thrive at certain levels of ketosis.

Remember it’s a total lifestyle that’s critical.  So in addition to the diet alterations, be sure to get the rest of your lifestyle in order.
  1. Get adequate and the best quality sleep you can nightly;
  2. Activity: Be sure to do some (lower intensity) exercise every day and then twice per week add in lifting heavier things (i.e. weights, bands, body weight), and once per week move as fast as you can (i.e. wind sprints).
Great sources for more information on activity for health, performance & longevity are Robb Wolf's site & Mark Sisson's site.  They also have some great info on primal/paleo eating as well.
So here's the protocol, I'm doing & that I have recommended that I see clients get the most out of.

Nutrition Strategies for a Ketogenic Diet 
  1. Decrease your total carbohydrate intake to less than 100 g daily. 
  2. Avoid highly refined carbohydrates (i.e. sugar and refined flours) because these will spike insulin and that will stop fat burning & stimulate fat storage.
  3. Exclude all grain products (especially wheat) for at least 60 days.
  4. Consume adequate vegetable matter.
  5. Limit yourself to less than 2 fruit servings per day.
  6. Avoid fruit or vegetable juices.
  7. Consume at least half your plate of low carb vegetables at each meal on average.  This provides at least 6 servings of highly nutrient dense vegetable matter per day.
  8. Include safe starches: potatoes (especially sweet potatoes, and other starchy tubers – these will provide carbohydrates to be readily converted into glucose by the body, but also come very complex starches that can be utilized by healthy gut flora (i.e. pre-biotics).
  9. Consume adequate protein.
  10. Depending on your individual needs, you will need differing levels of protein – usually 35% of total calories are good.
  11. Choose either grass fed, humanely raised animals or if you use conventionally raised then be sure to consume high omega 3 animals at least 3-4 times per week (i.e. oily fish).
  12. Don’t fear FAT!  You will be consuming around 50% of your calories from fat.  This is the most energy dense nutrient source, but it also has many health benefits.  In a ketogenic adapted person, this becomes your main fuel supply.
  13. Choose mostly anti-inflammatory fats – specifically foods high in omega-3 fats (animal sources like oily fish, pastured meats, cream & butter) and monounsaturated fats (like pastured meats, cream & butter, olives, avocadoes and their oils) and also saturated fats (pastured animal fats and coconuts and their milk (full-fat) and oil).  These are all highly anti-inflammatory.
  14. Use nuts sparingly due to high omega 6 fats.  Macadamia and Hazel nuts (philberts) have lower omega 6 content vs. monounsaturated fats.
  15. Adequate hydration – You will need to consume adequate water per day to ensure that you allow for adequate removal of byproducts associated with protein breakdown & ketosis.  Although some guidelines suggest 3-5 L per day, the best indicator is that your urine color (see chart below)



So I hope that you find that information useful and now you can bring that information with you to your health care provider.  Remember, I do not know your case at all, be sure to discuss this with your doctor or a health care provider who does know your case well, before attempting.  I am providing you with information to better understand a nutrition protocol and how it might be useful to you, but am in no way suggesting you do it.  As such, I am not responsible if you do try this unsupervised and develop issues as a result.  Use your common sense, and discuss this with someone who can help you do it safely.

If you do decide to talk to someone and move forward, remember that it is critical to keep a journal about how you are looking, feeling & performing each day to be able to see and record the changes that are happening in your life.  This way you'll know if this approach is moving you towards your goal or not.


Till next time.

Dietitian Dan T

Citations
http://www.ncbi.nlm.nih.gov/pubmed/12047499
http://www.ncbi.nlm.nih.gov/pubmed/19245705
http://www.appforhealth.com/wp-content/uploads/2011/07/Urine-chart.jpg