Fasting Challenges

Some people adjust quickly but for many people, the first week or two WILL BE TOUGH as you adjust both physically and mentally. You might go through carb or sugar withdrawal and get “hangry” or “keto flu” (actually feel nauseous). You might also feel light headed as your hormones try and adjust to the fact you are not giving your body regular glucose hits. You might feel starving. Stick with it for 2 weeks and those symptoms will lessen dramatically. Yes, you will still get hungry when you fast (even after you are used to it) but not the same gnawing hunger as you get at the beginning and it will pass quickly. It is actually OK to be hungry sometimes!  The reality is that hunger comes in waves, it goes away after a few minutes. Keep busy and drink some water or tea, go for a walk, get back to work or read a book. You will realise later that you have forgotten about it. Also after a few weeks, mentally you will be used to it so it won’t bother you so much if you feel hunger pangs (you can always eat if it gets unbearable). If you feel really shaky, dizzy or nauseous, just eat and try to fast again the next day.

Don't Snack!

When you are fasting, fast. When you are eating, eat. Don't snack in between meals. Keep your meals to no more than 90 minutes (shorter is fine and even better!) For example, if you are following a 18/6 fasting protocol (fasting 18 hours a day and eating within a 6 hour window), you can fit in 2 meals. So if you eat lunch at 1pm make sure you are done by 2.30pm.  And then if you eat dinner at 5.30pm, make sure you are done by 7pm. This 90 minute window gives you chance to have your meal, listen to your body and satiety signals and then eat a little more say an hour later if you are still hungry.  There is science behind this. In simple terms, every time calories are ingested (food or drink), your body releases insulin which kicks you out ketosis and fat burning mode. So every snack, however small or healthy, will change the hormonal balance in the body and work against you reaching your goals. 


If you follow the healthy low carb diet, there is no need to take supplements but if you are worried about it, take a multivitamin as your insurance policy.  If you feel tired or have a headache when fasting you are probably low on salt/sodium (which is present in most bread and processed foods) so have a teaspoon of Himalayan/pink salt.

If you get any muscle cramps or have trouble sleeping, take magnesium.

Weight loss plateau

If you hit a weight loss plateau (and you probably will at some point), vary fast lengths each day and increase fasting length to 24, 36 or 42 hours once or twice a week. Fasting up to 48 hours is fine if you have no underlying health issues.  To break a plateau, you can also lower your carbs to 20g a day which is a keto/ketogenic diet level (see keto info below)

Weighing yourself

The body is made up of more than 60% water so weight can change quite a lot within a day or week based on salt intake as well as the good old female hormones. A better indication of weight loss than a scale is measurements (stomach, hips, thigh circumference). Take these before you start FastaWeigh and then once a month. If you must weigh, do it once a week, after you wake up and before eating. Fasting stimulates growth hormone (to build muscle and bone) so you may see body composition changes before you see anything on the scale as muscle weighs more than fat. In short, the number on the scale is not always the best way to monitor progress. Your skinny jeans from 10 years ago, your belt notches and your waist circumference are a much better indicator of weight loss. You may be surprised that you are actually a smaller size after losing weight from fasting than you were when you were at that same weight previously so don’t get obsessed with a number on the scale (easier said than done I know!).  Trust the fasting process, not the scale.


Exercise is extremely important for health but as a weight loss tool, it is very overrated. The exception is HIIT (High Intensity Interval Training) which research shows is beneficial, particularly for those with insulin resistance (pre-diabetes or diabetes). So exercise to build strength, heart health, mental wellbeing and to fight off old age as long as possible and to have fun. Just remember, overexercising can be as detrimental as calorie restriction to your metabolic rate and you can’t run off a bad diet so don’t bother trying to.


Once you have reached your desired weight, you will be much more in tune with how and what carbs effect your body and hunger and how much or often you need to fast to maintain your weight. Most people will be able to slowly add carbs back in and keep eating ‘lowish’ carb/healthily most of the time and one 18-24 hr fast a week for maintenance. Our bodies are very individual so there is no one size fits all. You will be the judge. You’ll likely find you continue to skip breakfast and fast 14-16 hours a day and that is a good thing as it keeps all your hormones in balance. The beauty of fasting is in its flexibility and how in tune with your body you become so you will know what you need to do for maintenance (or if you just need to drop a few kilos after an indulgent holiday!)


Last of all, remember this. Fasting is simple, just don’t eat! It is simple but not necessarily easy at the beginning but it becomes habit once you have trained your fasting muscle and your hormones are working in balance and as they were originally designed to do!

Click here for the Low Carb Food List

The FastaWeigh plan and this website do not constitute medical advice. Please consult your doctor before fasting or substantially changing your diet if you have any underlying medical issues, take medications or have any health concerns. This includes but is not limited to diabetes, cardiovascular and heart conditions. Fasting is NOT recommended for children, pregnant or lactating women or for people with a history of eating disorders.

Read testimonials from FastaWeighers here