QUICK START FASTING GUIDE

Start slow, prioritize protein, take in extra salt, a clean fast helps you feel your best, and other tips for getting started.

[This is the difference of 6 months of fasting, 40 lbs, and 8 inches off my waist. Update: I’m now down 47 lbs.]

First off, read this short post about how to take your measurements. You’ll thank me later.

Start with 16:8. The first number means you fast for 16 hrs/day, and the second number means you eat your meals within 8 hours. (It does not mean that you eat for 8 hours straight!) One popular method would be to eat a large, hearty lunch with plenty of protein at 11 am. Then eat your hearty dinner centered on protein at 6 pm. Wrap up all eating by 7 pm. For people who like to eat dinner a bit later, you could eat between noon and 8 pm instead.

If 16:8 is too hard at first, you can start even slower. Let’s say you currently snack until 10 pm and then begin eating at 7 am, giving you only a 9-hour fast each night. In this case, it might work best to begin with a 12:12, cutting off eating at 8 pm and waiting until 8 am to have breakfast. Do that for a few days and then cut off eating at 7:30 pm and try to keep from breaking your fast until 9:30 the next morning. That’s a 14:10. Keep slowly pushing yourself until you get to 16:8, then hang out there for awhile and give your body time to adjust.

Prioritize Protein. This advice comes from a Doc I follow, Ted Naiman, MD, who wrote The P:E Diet which stands for The Protein to Energy Ratio Diet. Dr. Naiman has helped hundreds of patients in his practice reduce their weight through the “crowding out” principle of eating protein. At each meal, eat protein first and as much as you can. Keep eating until you can’t take another bite. Only after that, allow yourselves carbs. But pay attention to your hunger signals because you may not need the carbs.

Dr. Naiman’s protein leverage hypothesis states that hunger is primarily driven by the body’s need to get the correct amount of amino acids (protein) for repairing muscles, bones, tissues, skin, hair, nails, etc. If your body needs 60 grams of protein and you start by eating one piece of pizza, which has 12 grams of protein, your body may drive you to eat 5 pieces to get that protein requirement. Or, you could eat protein first, and then you might only want 1 piece of pizza, or none. I normally have burger patties in the fridge that can be nuked at any time, as well as steak and shredded beef.

For more about the importance of high protein, read this post. (Scroll down to: “I started fasting, now what do I eat?”)

Don’t snack! In the fasting community, we call not snacking “time-restricted eating” or TRE for short. TRE is important for allowing insulin to fall between meals. Remember that insulin is the fat-storage hormone. But your body doesn’t only release insulin in response to food, there is a basal amount of insulin that remains in the blood at all times (this is sometimes called the fasting insulin serum. I recently had mine tested because I’m that nerdy.)

This background amount of insulin is your body being proactive and preemptively preparing for the number of carbs it believes you will throw at it. In Why We Get Sick, Dr. Benjamin Bikman provides strong evidence that nearly every modern illness is related to high background insulin. You are wanting to lower this insulin not just when you fast, but also between meals. If you’re feeling the need to snack, you’re probably not eating enough protein at your meals. 

What if I Feel Shaky and Hangry? Unfortunately, the worse you feel when you fast, the more you need to be doing it. But if you feel too terrible, you’ll lose steam and quit. So back up and start with a shorter fast. Reduce your carbs and sugar in your meals to let your insulin fall. Your body is learning a new trick: how to burn its own fat for fuel. You’re working toward something called metabolic flexibility, the ability to burn carbs when available and easily switch to burning body fat when carbs are low. That’s the end goal, but give it time.

Take in Extra Salt: Signs you’re low on salt: dizziness, weakness, and brain fog. When insulin begins to fall, inflammation in the body also falls (as explained in detail in the Science Snippet on my Immune System Post). When you begin to shed this water weight, electrolytes exit the body too. This means that you’ll need to ingest quite a bit of extra sodium to replace what you’re losing. 

If you’re doing a 16:8, you can usually get enough by heavily salting your food. But if you’re doing a longer fast, you may need to either put small pinches of salt under your tongue or sprinkle a little in your water. (I’m now so accustomed to drinking slightly salty water that regular water tastes weird to me.) 

Salt is somewhat protective of the other electrolytes (potassium and magnesium) so if you can keep your salt up, you shouldn’t need to supplement too much with the other electrolytes. However, I do take magnesium glycinate (the only supplement I universally recommend to people.) There are two reasons for this: 1) our soil is largely depleted of magnesium and 2) diets high in processed foods (like the American diet) lead to widespread magnesium deficiency. But the type of magnesium is important because some forms can cause gastro upset. Magnesium glycinate and magnesium malate are two good options. Magnesium oxide and citrate are two common forms that often cause digestive upset from poor absorption.

Nail the “Clean Fast”: Clean fasting is a term that refers to avoiding much more than just calories when fasting. You are trying to flip a metabolic switch from fat-storing to fat-burning. But that switch is sensitive not just to calories, but to tastes. Anything that tastes like food can kick you out of fat-burning mode which makes you feel crappy.

To do a clean fast, you avoid anything with a flavor, such as gum (even sugar-free), flavored waters such as La Croix, diet sodas, and even many fruity herbal teas. Two things that nearly all fasters agree are fine are black coffee and black tea because of their bitter flavor profile. But don’t drink something like French Vanilla flavored black coffee. Some people even find that flavored teas such as Earl Gray can make them feel bad while fasting.

The reason you get kicked out of fat-burning mode by tasting food flavors and artificial sweeteners is that when your body senses that food might possibly be coming, it releases insulin. You will feel your very worst—shaky, hangry, fatigued—if you have an insulin release and no food comes because insulin drops your blood sugar. I’ve heard many fasting stories of people who couldn’t lose any weight fasting until they began clean fasting. 

One anecdote on that front: when I was trying keto several years ago, I asked on a forum if anyone knew why my ketones were always super low even though I was keeping my carb intake to under 20g/day. Someone suggested that I cut out artificial sweeteners. I thought, “That’s weird since they have no carbs or even calories.” (This was before I fully understood insulin.) But I tried it and bam, within a day of cutting out all artificial sweeteners, my ketones went from about 0.2 to 1.8.

That was my first introduction to the concept that there’s much more going on hormonally than just calories. Testing ketones is a roundabout way to test insulin at home since if insulin is high, ketones are low, and vice versa.

(If you don’t have a ketone blood monitor, never fear, you really don’t need one unless you’re a super nerd like me. I may or may not follow friends and family members around asking if I can take their blood glucose and ketone readings. I also recently subjected my husband to a mail-in A1C test. You can imagine how much fun it is living with me.😆)

When you’re ready to take your fasting to the next level, listen to this podcast that I went on as a guest. I explain a more advanced kind of fasting called alternate day:

[This newsletter is for informational purposes only and is not designed as a substitute for medical advice. Talk to your doctor before beginning any dietary changes, especially if you are on medications for diabetes. Fasting while taking certain medications such as Metformin and especially insulin can lead to dangerously low blood sugars. If your doctor does not support fasting, search for a physician who will support your fasting journey. Fasting is not recommended for those pregnant, breastfeeding, or for children and teens still growing and developing. For those with diabetes, personal fasting coaches are available through TheFastingMethod.com. I receive no compensation or ad revenue for anything in this newsletter including links to books, videos, websites, coaching services, podcasts, or supplements.]