ADHD and Autism

#202: Tamsin Lewis, MD- Keto, Eating Disorders & Carb Cycling for Endurance

by Deanna Mutzel, DC



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About Tamsin Lewis, MD

Dr Tamsin qualified with honours in Medicine & Surgery at Kings College London in 2004 intercalating a BSc in NeuroScience and was awarded MRCPsych from the Royal College of Psychiatrists in 2009.

She has since trained in a functional medicine approach incorporating advanced nutritional principles and appropriate use of bio-identical hormones


Show Notes

02:28 Dr. Lewis’ Experience with Anorexia: She was diagnosed with anorexia at age 11. Anorexia’s focus is the control of food, which preoccupies one from other things that are happening. Perhaps the biochemical and neurotransmitter changes that result from starvation, force ketosis and effect the brain. Dr. Lewis’ mother called it her “anorexic high”. The massive energy restriction from starvation forces the body to get energy wherever it can, including stress hormones. Dr. Lewis believes that there is a genetic component to anorexia. It is on the continuum of anxiety disorders.

07:40 The Salvation of Sport: One day Dr. Lewis realized that sport could save her from depression, anxiety and panic disorder. She had been on Prozac and similar drugs for years. As she came off the drugs, sport helped her brain rewire.

08:55 Dr. Lewis’ Advice about Anorexia: Approach diet differently. The traditional diet is heavily sugared food to instill cravings. However, the sugar makes you feel terrible. Use a high fat diet with supportive nutraceuticals like high does omega 3, magnesium, B6, and bioidentical B vitamins. One of the characteristics of anorexia is restlessness and over-exercising. It can be channeled to competition and performance. Fueling then becomes about performance, rather than to please people. Athletics becomes the new addiction. There needs to be balance. Many triathletes have a history of restricted eating.

16:58 Fat Adaptation and Athletes: It takes time to become fat adapted. There is an endurance performance benefit from periodization of carbohydrate intake. With periodization, the balance between recovery and adaptation to the training stimulus is balanced. Dr. Lewis has never seen a woman athlete do well on a ketogenic diet during endurance training.

21:35 Time Restricted Feeding Benefits and Challenges: Not eating for a large portion of the day resets the microbiome. Some of us can become chronically calorie restricted and will have problems with nutrient absorption, gut dysfunction and hormonal imbalance. It is a balance.

23:22 Glucose Monitors Help us engage with our Physiology: You see first hand the effects of food and stress. Stress effects Dr. Lewis’ blood sugar levels the most.

25:41 What Would Dr. Lewis do differently in a Do Over? She would have been an earlier adopter of a dietary change from carbohydrates to a higher fat diet. Endurance athletes commonly have gut dysfunction, so she would have addressed this. She would have supported with vitamins and adaptogenic herbs and come off the birth control pill earlier. Eliminating it improved performance. Birth control pills can cause stress fractures, impair recovery, cause tendon damage and impair muscle strength.

28:56 Try a More Natural Approach: You can spare your glycogen stores longer if you are fat adapted. Test your gut. Dr. Lewis finds high levels of parasites and dysbiosis in her endurance athlete patients. She uses a combination of the GI Map and Doctor’s Data comprehensive stool and parasitology. Sometimes, antibiotics are a good thing.

33:15 Dr. Lewis’ Love of Hot Yoga: Doing hot yoga creates a euphorigenic process. It helps her to focus on the moment. Dr. Lewis was in a coma following a skiing accident in 2004. Her parents were told that she would die. It was a long recovery process. She finds that yoga is very good for the nervous system and brain health.

42:04 Dr. Lewis’ Single Exercise: Running or cycling up mountains is her choice. You are in nature, moving, breathing, and stretching.

42:43 Dr. Lewis’ Desert Island Herb or Nutrient: She would choose a combination of ashwaganda, liposomal curcumin/resveratrol and a dose of omega 3s. She takes ashwaganda in the evening, because it is calming. Her most effective sleep aid is an Epsom salts bath with lavender.

44:07 Dr. Lewis Morning Routine: Ideally, she would do 15 minutes of yoga, setting a purpose for the day. She has licorice and peppermint tea in the morning, then drinks coffee. She would like to have a sauna in her house she can do hot yoga. She has a smoothie containing greens and fats. She has been experimenting with nootropics. They probably come at a biological cost.

47:30 Dr. Lewis’ Elevator Pitch: Create more social/community space to prevent social isolation. Bring about more public awareness around a lifestyle medicine approach. They are the most bang for your buck interventions.

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