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Can You Senior and Keto?

There are a number of myths floating around the blogosphere, social media and the “cyber-web” about who can and can’t use a ketogenic diet. Podcast #61 of Ketotalk.com tackles a number of these myths head on.


Today, we break down myths about: Insatiable Hunger, Fibromyalgia & Chronic Fatigue, Can Keto/IF Halt Weight Loss, Elevated Ketone Levels, Senior Citizens & Ketosis.  Tune in to find out if ketosis is right for those over age 65.

Keto Talk is cohosted by 10-year veteran health podcaster and international bestselling author Jimmy Moore from “Livin’ La Vida Low-Carb” and Arizona osteopath and certified bariatric physician Dr. Adam Nally from “Doc Muscles” who thoroughly share from their wealth of experience on the ketogenic lifestyle each and every Thursday.

KetoTalk From the Caribbean Sea


Dr. Nally recently spoke about Low-Carbohydrate/Ketogenic Diets on the 2016 Low Carb Cruise to the Eastern Caribbean.  While there, he and Jimmy Moore recorded another episode of KetoTalk with Jimmy and the Doc.

Listen in to KetoTalk Episode 20: A LIVE Q&A Session From The 2016 Low-Carb Cruise

Here’s what Jimmy and Dr. Nally talked about in Episode 20:
– We are in front of a LIVE audience of Ketonians
– How long will you experience hair loss when you go ketogenic?
– What role does resistant starch have on the keto diet?
– Is eating high-fat with high-carb harming my boyfriend?
– How does intermittent fasting help with keto?
– Whether to count total vs. net carbohydrates
– Whether you need to cycle carbs when building muscle
– What the best way to test your ketones is
– How to test blood ketones on a budget
– What the difference is between an NMR and basic lipid panel
– The dramatic changes in your cholesterol when going keto
– How long should you be on keto before running blood tests?
– Whether you should cut fat lower on keto to speed up weight loss
– Is having a lower body temperature a bad thing when eating keto?

You can listen at the iTunes page here, or download it for free to your favorite iTunes player.

Caffeine . . . Weight Loss Wonder Boy or Sneaky Scoundrel?

I’ve been looking for the answer for quite some time. . . what role does caffeine play in your and my weight management journey?  The answer gave me a headache. . . literally and figuratively.

As many of you, including my office staff, know, I love my Diet Dr. Pepper (and my bacon).  I found that being able to sip on a little soda throughout the day significantly helped the carbohydrate cravings and munchies during a busy and stressful day at the office.   Diet Dr. Pepper contains caffeine, however, I wasn’t really worried.  Caffeine has been well know to have a thermogenic effect which increases your metabolism and has been thought for many years to help with weight loss among the weight loss community.

Diet Dr. Pepper is, also, one of only four diet sodas on the grocery store shelves that doesn’t contain acesulfame potassium (click here to see why most artificial sweeteners cause weight gain).  The four diet sodas that I have been comfortable with my patients using are Diet Dr. Pepper, Diet Coke, Diet Mug Root-beer and Diet A&W Cream Soda.  These are the last four hold out diet sodas that still use NutraSweet (aspartame) as the sweetener.  Most of the soda companies have switched the sweetener in their diet sodas to the insulinogenic acesulfame potassium because it tastes more natural and aspartame has been given a media black eye of late.  However, NutraSweet (aspartame) is the only sweetener that doesn’t spike your insulin or raise blood sugar (click here to find out why that is important).

Yes, I know.  The ingestion of 600 times the approved amount of aspartame causes blindness in lab rats (but we’re not lab rats, and . . . have you ever met someone that drinks 600 Diet Dr. Peppers in a day?  The lethal dose of bananas, which are high in potassium that will stop your heart, is 400).  Aspartame can also exacerbate headaches in some (about 5% of people) and I’ve had a few patients with amplified fibromyalgia symptoms when they use aspartame.   But for most of us, its a useful sweetener that doesn’t spike your insulin response, halting or causing weight gain.

But, over the last few years, I’ve noticed that increased amounts of Diet Dr. Pepper & Diet Coke seem to cause plateauing of weight and decreasing the ability to shift into ketosis, especially mine.  I’ve also noticed (in my personal n=1 experimentation) that my ability to fast after using caffeine regularly seems to be less tolerable, causing headaches and fatigue 8-10 hours into the fast, symptoms that don’t seem to let up until eating. Through the process of elimination, caffeine seems to be the culprit.

Red Bull in caffeineAfter mulling through the last 10 years of caffeine research, most of which were small studies, had mixed results, used coffee as the caffeine delivery system (coffee has over 50 trace minerals that has the potential to skew the results based on the brand) and never seemed to ask the right questions, the ink from a study in the August 2004 Diabetes Care Journal screamed for my attention.

It appears that caffeine actually stimulates a glucose and insulin response through a secondary mechanism.   The insulin surge and glucose response is dramatically amplified in patients who are insulin resistant.  Caffeine doesn’t effect glucose or insulin if taken while fasting; however, when taken with a meal, glucose responses are 21% higher than normal, and insulin responses are 48% higher in the insulin resistant patient. Caffeine seems to only effect the postprandial (2 hours after a meal) glucose and insulin levels.  The literature shows mixed responses in patients when caffeine is in coffee or tea, probably due to the effect of other organic compounds (1).

Caffeine Effect on glucose insulin
Caffeine effect on plasma glucose and plasma insulin compared to placebo (1).

Caffeine also diminishes insulin sensitivity and impairs glucose tolerance in normal and already insulin resistant and/or obese patients.  This is seen most prominently in patients with diabetes mellitus type II (stage IV insulin resistance).  Caffeine causes alterations in glucose homeostasis by decreasing glucose uptake into skeletal muscle, thereby causing elevations in blood glucose concentration and causing an insulin release (2-6).

Studies show that caffeine causes a five fold increase in epinephrine and a smaller, but significant, norepinephrine release.  The diminished insulin sensitivity and exaggerated insulin response appears to be mediated by a catacholamine (epinephrine, norepinephrine & dopamine)  induced stress response (5).  Caffeine has a half life of about 6 hours, that means the caffeine in your system could cause a catacholamine response for up to 72 hours depending upon the amount of caffeine you ingest (7).

The reason for my, and other patient’s, headaches and fatigue after a short fast was due to the exaggerated stress hormone response.  Increased levels of insulin were induced by a catacholamine cascade after caffeine ingestion with a meal, dramatically more amplified in a person like me with insulin resistance. The caffeine with the last meal cause hypoglycemia 5-7 hours into the fasting, leading to headaches and fatigue that are only alleviated by eating.

Even when not fasting, the caffeine induced catacholamine cascade causes up to 48% more insulin release with a meal, halting weight loss and in some cases, causing weight gain.

Caffeine is not the “Wonder-Boy” we thought it was.

How much caffeine will cause these symptoms? 50 mg or more per day can have these effects.


Ingestion of caffeine has the following effects:

  • 20-40 mg – increased mental clarity for 2-6 hours
  • 50-100 mg – decreased mental clarity, confusion, catacholamine response
  • 250-700 mg – anxiety, nervousness, hypertension & insomnia
  • 500 mg – relaxation of internal anal sphincter tone (yes . . . you begin to soil yourself)
  • 1000 mg – tachycardia, heart palpitations, insomnia, tinnitus, cognitive difficulty.
  • 10,000 mg (10 grams) – lethal dose (Yes, 25 cups of Starbucks Coffee can kill you)

The equivalent of 100 mg of in a human was given to a spider, you can see the very interesting effect on productivity.  How often does the productivity of the day feel like the image below?

Spider Normal
Normal Spider (9)
Spider Caffeine
Spider on caffeine (9)

Beware that caffeine is now being added to a number of skin care products including wrinkle creams and makeup.  Yes, caffeine is absorbed through the skin, so check the ingredients on your skin care products.

Diet Dr. Pepper, my caffeine delivery system of choice, has slightly less caffeine (39 mg per 12 oz can or 3.25 mg per oz) than regular Dr. Pepper.  I found myself drinking 2-3 liters of Diet Dr. Pepper per day (long 16-18 hour work days in the office).  After doing my research, I realized that my caffeine tolerance had built up to quite a significant level (230-350 grams per day).

So, a few weeks ago, I quit . . . cold turkey.

Did I mention the 15 withdrawal symptoms of caffeine? (8)

  • Headache – behind the eyes to the back of the head
  • Sleepiness – can’t keep your eyes open kind of sleepiness
  • Irritability – everyone around you thinks you’ve become a bear
  • Lethargy – feels like your wearing a 70 lb lead vest
  • Constipation – do I really need to explain this one?
  • Depression – you may actually feel like giving up on life
  • Muscle Pain, Stiffness, Cramping – feel like you were run over by a train
  • Lack of Concentration – don’t plan on studying, doing your taxes or performing brain surgery during this period
  • Flu Like Illness – sinus pressure and stuffiness that just won’t clear
  • Insomnia – you feel sleepy, but you can’t sleep
  • Nausea & Vomiting – You may loose your appetite
  • Anxiety – amplified panic attacks or feeling like the sky is falling
  • Brain Fog – can’t hold coherent thoughts or difficulty with common tasks
  • Dizziness – your sense of equilibrium may be off
  • Low Blood Pressure & Heart Palpitations – low pressure and abnormal heart rhythm

I experienced 13 of the 15 that lasted for 4 days.   I do not recommend quitting cold turkey unless you have a week off and someone to hold your hand, cook your meals and dose your Tylenol or Motrin.  My wife thought I was dying. . . I thought I was dying on day two.  I actually had a nightmare about buying and getting into my own coffin.  It can take up to three weeks to completely recover from caffeine withdrawal.

The other way to quit is to decrease your caffeine intake by 50 mg every two days.   That means decrease caffeine by:

  • 1 can of soda every two days
  • 1/4 cup of coffee every day
  • 1/2 can of Energy Drinks every two days
  • 1 cup of tea every two days

The benefit of this method is that withdrawal symptoms are much less severe without the caffeine headache and the ability to remain productive.  It will take longer, but quitting cold turkey is not a pretty picture.  Been there . . . done that, . . . and I’m not going back. I actually lost another half inch off my waistline by day 5 of caffeine discontinuation.

What is the take home message here?  If you have any degree of insulin resistance, caffeine makes it worse and will amplify your weight gain as well as decrease the productivity of your day.


  1. Lane JD, Barkauskas CE Surwit RS, Feinglos MN, Caffeine Impairs Glucose Metabolism in Type II Diabetes, Diabetes Care August 2004 vol. 27 no. 8 2047-2048; doi:10.2337/diacare.27.8.204
  2. Jankelson OM, Beaser SB, Howard FM, Mayer J: Effect of coffee on glucose tolerance and circulating insulin in men with maturity-onset diabetes. Lancet 1527–529, 1967
  3. Graham TE, Sathasivam P, Rowland M, Marko N, Greer F, Battram D: Caffeine ingestion elevates plasma insulin response in humans during an oral glucose tolerance test. Can J Physiol Pharmacol 79:559–565, 2001
  4. Greer F, Hudson R, Ross R, Graham T: Caffeine ingestion decreases glucose disposal during a hyperinsulinemic-euglycemic clamp in sedentary humans.Diabetes 50:2349–2354, 2001
  5. Keijzers GB, De Galan BE, Tack CJ, Smits P: Caffeine can decrease insulin sensitivity in humans. Diabetes Care 25:364–369, 2002
  6. Petrie HJ, et al. Caffeine ingestion increases the insulin response to an oral-glucose-tolerance test in obese men before and after weight loss. American Society for Clinical Nutrition. 80:22-28, 2004
  7. Evans SM, Griffiths RR, Caffeine Withdrawal: A Parametric Analysis of Caffeine Dosing Conditions, JPET April 1, 1999 vol. 289no. 1 285-294
  8. Noever R, Cronise J, Relwani RA. Using spider-web patterns to determine toxicity. NASA Tech Briefs April 29,1995. 19(4):82. Published in New Scientist magazine, 29 April 1995