What Do You Eat On A 500 Calorie Fast Day?

Join SusieT as she answers the burning question, “What do you eat on 500 calorie fast days? Learn why she doesn’t feel deprived living an alternate day fasting (ADF) lifestyle, which is sometimes called every other day (EOD) dieting, or  JUDDD. SusieT will show you how she calculates her minimum daily protein requirement. Do you want to know why she always plans dinner (and protein) first? She covers all this, plus shows you a couple of alternate day fasting (ADF) meal plans made of one meal per day and also made of multiple meals per day. We think you will be surprised by how much food you can eat for a 500 calorie ADF budget.

One of the most common responses I get when I tell people about my alternate day fasting (ADF) lifestyle is, “Oh my gosh! You only eat 500 calories every other day? I could NEVER do that! What do you eat on your fast days? Don’t you feel deprived?”


(click on image to enlarge)
Roasted Pork Tenderloin makes a great Fast Day (FD) protein choice and Chopped Salad adds lots of “chew factor” which increases satiety.

It is entirely possible to experience joy with this kind of lifestyle. Let me tell you why. Every other day I can eat anything I want and still lose weight. No diet. No watching what I eat. No countin’ nothin’. Just like a regular person. And in eating 500 calories every other day, my body still heals from inflammation. My fast days are my healing days. In short, it’s all about the healing. The weight loss is just a fringe benefit of every other day dieting.

On Fast Days (FDs) I do three main things:
Make sure to eat a LOT of fiber or high-chew foods
Make sure to get a LOT of lean protein
Make sure to keep food as “normal feeling” as possible

You see, even though I fast with calorie restriction on alternate days, I don’t want to “feel” like I’m doing it. I trick my mind, which is my biggest ally or biggest enemy, into believing that a 500 calorie FD is just another day at the office. 99% of the time, that’s easy to do now that I’ve been living an ADF (alternate day fasting) lifestyle for awhile.

When first starting out in ADF or EOD (every other day) some might find they need more than one meal a day. Heck, you may always want to eat more than one meal a day. Many like to eat 2 meals a day, spaced 12 hours apart like suggested in THE FAST DIET by Michael Mosley and Mimi Spencer. Many find it’s easier to do a 500 calorie day when eating only one big meal. I’m like that. I figured out that once I started eating for the day, I wanted to continually eat during the remaining day and that my hunger level was much higher. It’s a YMMV (your mileage may vary) thing, and no two fasters are alike! So listen to your body over time and take cues from it. After 2-3 weeks, you get used to your schedule on fast days, so I do recommend making a plan for FDs and sticking to that plan every FD.

I eat lower fat and low carb on fast days because fat has 9 calories per gram and protein and carbs only have 4 calories per gram, so I get more food and that’s the bottom line for me. I eat low carb because high glycemic carbs spike my blood sugar and make me much hungrier.  I’m a volume eater and want to have a full belleh after a meal and I do not want to get hungry again 2 hours later. But ADF or EOD is not a “low fat” or “low carb” diet. It’s anything you want it to be. You can eat low fat, low carb, paleo, primal, lchf (low carb high fat)—heck, you can fat fast—whatever you want, as long as you contain it to 500 calories per day for women and 600 calories per day for men.

It’s important to get enough protein on a daily basis—fasting or non-fasting (some call non-fasting days feast days). You need a certain amount of protein each day because your body uses it to function and make repairs and if you don’t eat enough protein, it will scavenge and recycle broken proteins and when that is gone, will go after lean body mass (muscles and tissues).

How much protein do we need each day? The U.S. RDA sets minimum protein requirements or Estimated Average Requirements (EAR) —defined as “the minimum daily needs for protein to maintain short-term nitrogen balance in healthy people with moderate physical activity.” It’s roughly estimated at 0.8g/kg of lean body mass (LBM). You can estimate lean body mass here.  Then simply multiply LBM in kilograms (2.2kg=1 lb), to learn your minimum protein needs.

My minimum protein need is:

127lbs LBM/2.2=57.7kg

57.7kg X 0.8g/kg = 46g or high quality protein per day

One thing to mention, when discussing protein requirements, grams of protein refers to the actual amount of protein within an ingredient or food, not it’s actual weight. For instance 1 ounce of pork tenderloin, raw, weighs 1 ounce, or 28.35 grams. It contains protein, fat, water, vitamins and minerals, and waste products within that 1 ounce or 28.35 grams. But it contains 6g of actual protein in that 1 ounce unit. You can find the nutritional content of many foods in the USDA food database or online at many fitness websites such as FitDay. To get my 46g of protein I would need to eat a minimum of 7-8 ounces from a quality protein source such as meat, poultry, seafood, eggs, cheese, cultured milk such as yogurt of kefir, beans and lentils, etc.

One of the tricks I’ve learned through trial and error is to plan my fast day meals in reverse beginning with dinner first and planning protein first, as well. Most of the time I eat one meal a day—usually the evening meal or late afternoon meal. Because of that, the meal looks and feels pretty much like any other meal. But sometimes I want other small meals and when that happens, I want to be sure to have enough calories in my calorie bank to get me a yummy dinner. That’s why my plan always begins with the dinner protein first.

I bought a digital scale on Amazon that takes the guesswork out of food quantities. It’s easy to over-estimate serving size. We call that portion distortion and it’s death to a calorie restricted day! It’s easy to over-fill measuring cups and measuring spoons. And it’s hard to measure the same amount each time. A scale removes the shades of grey from portioning food. I love that it reads in many different units. Sometimes I want ounces and other times I need grams.

Here are a couple of examples of my 500 Calorie Fast Days (FDs). When eating 1 meal per day, then I plan on using the full 500 calories for that meal. When eating multiple meals per day, I plan on 300-350 calories for dinner and split the remaining calories between 1-2 meals. And you may be surprised at how much food you can eat for 150-200 calories!

SAMPLE – 1 Meal/Day (505 Cals)

Daily Totals: 505 Calories; 25g Fat (45.3% calories from fat); 46g Protein; 23g Carbohydrate; 6g Dietary Fiber; 317mg Cholesterol; 17g Net Carbohydrate

Dinner at 4PM
The Big Pig Salad (495 cals)
4 1/2 ounces roasted pork tenderloin
4 ounces romaine hearts
1 1/2 ounces super greens trio (kale, chard, spinach), organic
1 large egg
1 ounce blue cheese
1 ounce avocado
2 tablespoons grated carrot
4 ounces cucumber
2 ounces red onion
1 ounce grape tomatoes
3 tablespoons Walden Farms Balsamic Dressing
1 tablespoon Country Dijon Mustard
2 tablespoons Bragg’s Unfiltered Apple Cider Vinegar
3 kalamata olives

Dessert at 8PM
1 serving sugar free gelatin (10 cals)

SAMPLE – Multiple Meals/Day (499 Cals)

Daily Totals: 499 Calories; 13g Fat (22.6% calories from fat); 52g Protein; 51g Carbohydrate; 18g Dietary Fiber; 91mg Cholesterol; 33g Net Carbohydrate

Dinner at 7PM (295 Calories; 9g Fat (27.4% calories from fat); 30g Protein; 25g Carbohydrate; 7g Dietary Fiber; 55mg Cholesterol; 18g Net Carbohydrate)
1/6 of 9-inch Cheeseburger Pie – (topped with homemade Garlic Dijonnaise, lettuce, tomato, dill pickle relish and Italian parsley)
5 oz Ugly Green Beans
1 small Tomato, sliced

Dessert at 9PM (16 Calories; trace Fat (10.9% calories from fat); 1g Protein; 1g Carbohydrate; trace Dietary Fiber; 0mg Cholesterol; 1g Net Carbohydrate)
1 serving sugar-free gelatin
1 serving homemade whipped topping

Lunch at 1PM (117 Calories; 4g Fat (25.0% calories from fat); 15g Protein; 11g Carbohydrate; 7g Dietary Fiber; 31mg Cholesterol; 4g Net Carbohydrate)
1 serving Dandan Noodles
2 oz Grilled Chicken

Breakfast at 10AM (70 Calories; trace Fat (1.4% calories from fat); 6g Protein; 14g Carbohydrate; 4g Dietary Fiber; 5mg Cholesterol; 10g Net Carbohydrate)
1 serving Blueberry Breakfast Pudding Yogurt

Author: Susie T. Gibbs

SusieT is passionately committed to seeking studies and research detailing the most effective strategies for killing inflammation, boosting health, increasing energy and expanding longevity through nutrition. Seeking health through ancestral principles and making darn good food while traveling along life’s path to better health occupies a key place in her personal food philosophy. SusieT develops recipes and writes about cooking, food, health and nutrition news. Find her latest work in CarbSmart Magazine, a digital magazine from the leaders in low carbohydrate information. A two-year survivor from late stage, hormone-positive breast cancer, SusieT encourages everyone to meet their kitchen and begin a love affair with life and cooking good, clean, nourishing meals. The life you save could be your own. Email SusieT with questions and suggestions for new 5:2 and 4:3 ADF/EOD recipes.

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