A demanding reader, Phishman from Maine asks some very big questions:
First off, let me say that I was just recently introduced to your blog and find it very useful. Hopefully you have a minute or two to respond to this email, or post your answers on your web site.
I have been living a low-carb lifestyle on and off for about 2.5 years now, and absolutely love it. Not only do I do it for weight management, but it also helps with energy levels, building muscle, working vegetables and healthy fats into the diet, cures any symptom under the sun from a bad diet (over-eating, heartburn, etc). In other words, no one need to convince me that this is among some of the more healthy nutrition plans known to the human body.
It seems that between 2002 and 2003 low-carb dieting, specifically Atkins, was at its
peak. You could find their food everywhere, LC eating was getting a bunch of positive press, and people really started changing their minds. Then, the death of an overweight, heart-troubled Robert Atkins was plastered all over the media, as well as a disastrous comment by one of their spokespeople about saturated fat, and since then Atkins has filed Chapter 11, their advertising campaign is almost non-existent, and at least up here, their food is all but impossible to find.
I’ve seen nothing defy typical common sense for the lay-person when it comes to nutrition the way Atkins’ philosophy does, and I always find myself battling with people, and constantly citing the very small handful of studies that have gained enough notoriety to prove his position in the world of nutrition.
With all of this mind, I’d love to play devil’s advocate for a moment, and give you the most common critiques of the diet that even I, a staunch supporter, have trouble defending at times. I would love for you to take a moment to respond to these common criticisms of low carb eating:
- No one, and I mean NO ONE is arguing the fact that people can loose weight
quickly and significantly on Atkins. No one is even arguing that certain fats aren’t good for you such as those from nuts/vegetable oils. However, almost every single nutritional study to date suggests that saturated and trans fats are harmful, and cause drastic increases of bad cholesterol. To simplify, are we to believe that it’s the crust in pizza that’s raising our cholesterol levels and not the cheese, or the potato, not the butter melting on it?
- Everyone knows that a balanced diet is key. No one building block of food (carbs/protein/fat etc) should be over or under-emphasized. What do you say to those who recommend balance?
- Don’t low carb diets deny us the vitamins and minerals of so many important fruits and even some vegetables that simply can’t be replaced by supplements?
- Isn’t it dangerous to deprive our bodies, especially our brains of glucose and natural sugars?
- Don’t carbohydrates play a vital role in exercise, energy, and muscle growth? Could you honestly recommend, for example, that someone run a 10k race on only 20-50 carbs each day for several weeks beforehand?
I’d love to hear your response so I can respond a little better to some of the ‘water cooler’ critics who are honestly using little more than normal intuition to come to their conclusions. Feel free to publish this on your blog.
Ok phishman, you asked for it, Dr. Vernon responds:
Robert Atkins was a champion of the truth. He was also a brilliant witty entreprenuer with enough intestinal fortitude to face multiple attacks including a Senate hearing to defend what you have already experienced-keep the sugars and starches out of the diet and health improves. His cardiologist stated in a televised interview that during a cardiac catheterization a year or two before his death, his arteries did not require any intervention. I hope I can say that about myself at age 72.
Dr. Atkins died of a head injury sustained from a fall. His heart kept going for weeks. (Again, I should have such a heart at that age.) His brain was injured. I don't know of anything about low carb that protects one from accidents like slipping on ice. Of course the sequelae of two brain surgeries and the best American medicine had to offer was fluid retention from medications to decrease brain swelling and maintain blood pressure in the presence of such an injury. As a result a comatose Dr. Atkins bloated and swelled.
Speaking of attacks-after his death, a physician associated with a radical animal rights group asked for Dr. Atkins records-and the City of New York sent these records without a release! This same physician/group then crafted a press release calculated to generate in the media exactly the message you took home by releasing half truths. So there. Dr. Atkins "obesity" was caused fluids related to life-saving measures and this was delivered to the media as evidence of the failure of low carb eating. This was dishonesty and misinformation at its most vile.
Next: What a relief. Can I really believe you when you say that no one argues that one can lose weight using this approach? It seems I still fight this battle. I am glad that the common sense is now that carbs and gain of fat are linked. It is true.
You will need to tell me what nutritional studies show that saturated fats are harmful in the absence of carbohydrates. I know of none that show this. All the saturated fat studies so far have had lots of carbs. DO FAT AND SUGAR TOGETHER TRIGGER FAT STORAGE? YES.
Now, pay attention, because some brilliant scientists have been working on answering this question.
In the fall of 2006, at the annual meeting of the North American Association for the Study of Obesity (NAASO), Dr. Steve Phinney and Dr. Jeff Volek presented a poster. I am quoting directly from the abstract conclusions: The absolute concentration of total SFA in plasma TG was reduced by 57% after the VLCKD, compared to 21% after the low fat diet. We conclude that a VLCKD reduces both the % and absolute amount of SFA in plasma TG to a greater degree than the low fat diet, despite the relatively high proportion of fat and SFA consumed with the VLCKD. The abbreviation SFA=saturated fatty acids, and VLCKD means very low carbohydrate ketogenic diet, ie-Atkins induction.
Here is the translation for those who don't want to wade through the science talk: The saturated fat in the blood stream went way down on a diet high in saturated fat and low in carbs. Know what else they found? The type of fat your body makes when it is actively storing fat went way down as well. Wait! I think Dr. Atkins said something like that-you store less fat when you eat fat if you leave out the carbs! So in response to your question-eat the butter and cheese on the pizza, and ditch the crust.
What I say to the people who recommend balance is that the Emperor is naked. Balance is as balance does. Is balance equal volume measures (cups of food), equal energy amounts (joules) or is balance what someone writes down without any knowledge of the consequence of that recommendation in an individual person? As a bariatric physician, I learned that template solutions for complex problems don't work. Dropping down to 20 grams of carbs/day from leafy green vegetables and eating the remainder of your energy needs from meat and fat, then adding low glycemic carbs back in slowly (after you have attained metabolic health) allows each person to find their own balance. If that is 20 grams of carbs from leafy greens every day for the rest of their life, then that's what it is.
The best analogy to explain this is sun exposure. Should all humans have the same amount of sun exposure? No. (Duh). I wear a hat, long sleeves and sunscreen and avoid the outdoors between 11 am and 4 pm. All the time and even on the beach. I have friends who just get tan and never burn. DO what fits you and your metabolism.
And while I am ranting about this, Here is my personal soapbox issue:
Individuals who maked dietary recommendations based on what they think instead of what really happens in patients. This certainly happened with the low fat recommendations. See Gary Taubes article "The Soft Science of Dietary Fat".
The problem has not stopped with low fat vs high fat-but continues on when lay press diet books give all sorts of advice about healthy fats without at least some patient evidence. Dr. Atkins observed the benefits of the carb control approach in himself and in his patients-then he wrote about their outcomes.He didn't just decide what should happen and then write a book about his opinion. He knew what happened because he saw it happen. I had the same experience.
On to question # 3)
The answer to your question is "No".
This has acutally been analyzed and representative low carb 20 gram menus are perfectly fine in this regard. Leafy greens as recommended are the enzymatic powerhouse of the plant and have these vitamins in abundance. They also have the other substances you mention that may contribute to health.Remember what I said above? That individualization is key to diet and health? Same here. Why not take a multiple vitamin to cushion the individual dietary preferences and metabolic differences?
4) If eating a low carb diet deprived your body and brain of glucose you'd be dead. You are not. Therefore, it does not deprive your body or your brain of anything. Now for the fun explanation:
When scientists calculate the minimum amount of fuel needed to keep you alive if you just lay still and breathe, it is the equivalent of about 100 grams of glucose a day. Your brain is perfectly happy to use a fuel called ketones to fulfill its energy needs. Only your red blood cells, a few parts of your eye and maybe a couple of other cells can use only glucose as an energy source. If you add up the energy needs of cells that only use glucose their energy requirement is about 30 grams of glucose/day. Your liver and kidneys (yes your kidneys) can easily make that much glucose from other sources: amino acids from protein and glycerol from your fat.
The other cells in your body, like muscle cells, can use fatty acids and ketones as fuel. So no problem on a low carb ketogenic diet. You eat protein and fat, both of which can be used to make the minimal amount of glucose needed on a daily basis. There is no minimum daily requirement for dietary carbohydrate.
Here is a conundrum:
Children with seizures are treated with a ketogenic diet much stricter than even Atkins induction. This approach is nearly miraculous in many cases in decreasing seizures. In other words, their brains work better using ketones for fuel. I don't have seizures, but my brain works better on a low carb ketogenic Atkins Induction type diet, too.
Another smart scientist (Eric Kossoff at Johns Hopkins) tried the induction approach on kids with seizures and found that it worked great. Here is the Pub Med abstract and the link.
A modified Atkins diet is effective for the treatment of intractable pediatric epilepsy.
Kossoff EH, McGrogan JR, Bluml RM, Pillas DJ, Rubenstein JE, Vining EP.
John M. Freeman Pediatric Epilepsy Center, Departments of Neurology and Pediatrics, the Johns Hopkins Medical Institutions, Johns Hopkins Hospital, 600 North Wolfe Street, Baltimore, MS 21287-1000, U.S.A. ekossoff@jhmi.edu
PURPOSE: The Atkins diet may induce ketosis as does the ketogenic diet, without restrictions on calories, fluids, protein, or need for an inpatient fast and admission. Our objective was to evaluate the efficacy and tolerability of a modified Atkins diet for intractable childhood epilepsy. METHODS: Twenty children were treated prospectively in a hospital-based ambulatory clinic from September 2003 to May 2005. Children aged 3-18 years, with at least three seizures per week, who had been treated with at least two anticonvulsants, were enrolled and received the diet over a 6-month period. Carbohydrates were initially limited to 10 g/day, and fats were encouraged. Parents measured urinary ketones semiweekly and recorded seizures daily. All children received vitamin and calcium supplementation. RESULTS: In all children, at least moderate urinary ketosis developed within 4 days (mean, 1.9). Sixteen (80%) completed the 6-month study; 14 chose to remain on the diet afterward. At 6 months, 13 (65%) had >50% improvement, and seven (35%) had >90% improvement (four were seizure free). Mean seizure frequency after 6 months was 40 per week (p = 0.005). Over a 6-month period, mean serum blood urea nitrogen increased from 12 to 17 mg/dl (p = 0.01); creatinine was unchanged. Cholesterol increased from 192 to 221 mg/dl, (p = 0.06). Weight did not change significantly (34.0-33.7 kg); only six children lost weight. A stable body mass index over time correlated with >90% improvement (p = 0.004). CONCLUSIONS: A modified Atkins diet is an effective and well-tolerated therapy for intractable pediatric epilepsy.Oh, yeah, and low carb ketogenic diets help migraines in many patients. Dr. Kossoff is working on a study on this, I think.
Again, the short answer to your question is that you don't need carbs. Now, for the fun explanation:
Want to know about carb restriction and exercise? Look up a study done by Dr. Stephen Phinney on
trained bicycle racers.
The human metabolic response to chronic ketosis without caloric restriction: preservation of submaximal exercise capability with reduced carbohydrate oxidation.
Phinney SD, Bistrian BR, Evans WJ, Gervino E, Blackburn GL.
To study the effect of chronic ketosis on exercise performance in endurance-trained humans, five well-trained cyclists were fed a eucaloric balanced diet (EBD) for one week providing 35-50 kcal/kg/d, 1.75 g protein/kg/d and the remainder of kilocalories as two-thirds carbohydrate (CHO) and one-third fat. This was followed by four weeks of a eucaloric ketogenic diet (EKD), isocaloric and isonitrogenous with the EBD but providing less than 20 g CHO daily. Both diets were appropriately supplemented to meet the recommended daily allowances for vitamins and minerals. Pedal ergometer testing of maximal oxygen uptake (VO2max) was unchanged between the control week (EBD-1) and week 3 of the ketogenic diet (EKD-3). The mean ergometer endurance time for continuous exercise to exhaustion (ENDUR) at 62%-64% of VO2max was 147 minutes at EBD-1 and 151 minutes at EKD-4. The ENDUR steady-state RQ dropped from 0.83 to 0.72 (P less than 0.01) from EBD-1 to EKD-4. In agreement with this were a three-fold drop in glucose oxidation (from 15.1 to 5.1 mg/kg/min, P less than 0.05) and a four-fold reduction in muscle glycogen use (0.61 to 0.13 mmol/kg/min, P less than 0.01). Neither clinical nor biochemical evidence of hypoglycemia was observed during ENDUR at EKD-4. These results indicate that aerobic endurance exercise by well-trained cyclists was not compromised by four weeks of ketosis. This was accomplished by a dramatic physiologic adaptation that conserved limited carbohydrate stores (both glucose and muscle glycogen) and made fat the predominant muscle substrate at this submaximal power level.
Ok, here is what Dr. Phinney did. He took trained bicycle racers and fed them a very low carbohydrate ketogenic diet long enough for them to adapt to using fat as an energy source. (at least 2 weeks at a minimum, but he fed them this way for a month). He tested them for performance and did all sorts of other tests including muscle biopsies for glycogen.
You can read it for yourself-the racers did as wells on the diet as before. Although they had less muscle glycogen stored, their glycogen dropped less when they were keto-adapted. They didn't need to use their glycogen because they were so good at burning fat.
I have depleted my brain ketones writing all this so I am going to go find some fat. Take that to the water cooler. Thanks for asking.