Juice cleanse experience day by day?

The first day of the juice cleanse often feels easier than expected. The second day of the juice cleanse is the hardest for many, with hunger in the afternoon, feeling cold, or mild headaches. From the third day on, things usually settle down.

This is a typical progression, not a rigid schedule. Every body reacts differently. In a large observational study involving 1,422 people fasting, mild discomfort occurred primarily in the first few days, with serious side effects in less than one percent (Wilhelmi de Toledo et al., 2019).

The body draws on its reserves

On the first day of the juice cleanse, your body primarily sources energy from glycogen stores in the liver and muscles. These stores last for about 24 to 48 hours (Schweizer Zeitschrift für Ernährungsmedizin, 2022). That is why the first day of the juice cleanse often feels good; some are even surprised by how little they miss. Hunger tends to occur around usual meal times, as your body is accustomed to fixed meals.

Those who start well-prepared notice the transition less. One or two light relief days take the edge off the first day of the juice cleanse, as shown in our article on juice cleanse preparation.

On the second day of the juice cleanse, the sugar stores are largely empty. The body shifts more significantly to its fat reserves; this transition typically begins on the second or third day of fasting (Schweizer Zeitschrift für Ernährungsmedizin, 2022). This takes energy, and many feel this as fatigue, feeling cold, or afternoon hunger. Your mood might also be more sensitive on this day, with small annoyances seeming larger than usual. This is known and passes for most people.

In addition, many also forgo coffee. In a study, regular coffee drinkers without caffeine had headaches on 30 percent of the days, compared to only 10 percent with coffee (Randa et al., 2026). Part of the slump on the second day of the juice cleanse is therefore caffeine withdrawal and not a sign that the cleanse isn't right for you. You can find out how to mitigate this in our article on coffee during the juice cleanse.

The slump often lasts only one to two hours. Many find it easier if they plan rest, warmth, and warm tea for the afternoon instead of exercise and a full schedule. You can find more about headaches, feeling cold, and hunger in our article on discomfort during the juice cleanse.

Many report that something changes from the third day of the juice cleanse. Hunger signals become less frequent, and the day runs more evenly. In the large observational study, 93 percent of those fasting reported having no feeling of hunger, and well-being increased over the course (Wilhelmi de Toledo et al., 2019). However, participants were medically supervised, and there was no control group.

The Doctors' Association for Fasting and Nutrition (ÄGHE) also describes that for most, the mood brightens after initial discomfort (ÄGHE, 2025). For many, the third day is therefore the moment when they see their habits more clearly, such as the reach for sweets in the afternoon.

What is different with five or seven days

During a longer cleanse, every additional day resembles the third rather than the second. Sleep can be more restless; in the study, this was the most common minor symptom at nearly 15 percent. How long your cleanse should be is addressed in our article Juice Cleanse 3, 5, or 7 days.

One honest point must be mentioned. A small study from 2025 found shifts in the oral and gut flora after three days of pure juice diet; the researchers attribute this to high sugar content and a lack of fiber (US study, 2025). A vegetable-focused cleanse and a good transition period afterward are therefore important.

If a day of the juice cleanse feels significantly bad, with severe dizziness, heart palpitations, or discomfort lasting for days, this is no longer a normal slump. Then you should stop and seek medical advice. Our article canceling or pausing a juice cleanse shows you how to proceed.

After the last day of the juice cleanse, your gut first needs to get used to solid food again. The German Nutrition Society (DGE) describes a gradual build-up of food after therapeutic fasting, starting with increasing amounts—about 800 kilocalories on the first day and around 1,200 on the third (DGE, 2018). The ÄGHE (Medical Association for Therapeutic Fasting and Nutrition) recommends three transition days after fasting (ÄGHE, 2025).

After a short juice cleanse, you can increase your intake a bit faster. Many find that the first meals back are surprisingly intense, and small portions are filling quickly. The taste of simple vegetables or an apple seems much stronger, and many notice sooner when they have had enough. It is worth taking this mindfulness with you. Eating slowly and chewing well during the first few days prevents that feeling of being overly full, which can quickly leave the impression that fasting wasn't the right choice for you. You can find out what this looks like day by day in our article on how to properly transition after a juice cleanse.

No day of a juice cleanse is like the other. The first is often easier than expected, the second is the hardest for many, and from the third, things usually become calmer. Behind this process is the adjustment of the metabolism and, for many, the lack of coffee.

Those who know the typical progress can take the slump on the second day of the cleanse more calmly and recognize warning signs earlier. The transition days are an integral part of the cleanse, as they determine what remains of your efforts.