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Is it good to juice fast once a week?


Juice fasting, also known as juice cleansing, has become an increasingly popular diet trend in recent years. The premise is simple – consume nothing but fruit and vegetable juices for a set period of time, usually ranging from 1 to 7 days. Advocates claim that juice fasts can help remove toxins from the body, promote weight loss, and improve overall health. But is juicing once a week actually good for you? Let’s take a closer look at the potential benefits and drawbacks.

What is Juice Fasting?

Juice fasting involves extracting the juices from fresh fruits and vegetables and drinking that liquid in place of eating solid foods for a short period of time. The juices provide most of the vitamins, minerals, and plant chemicals you would get from whole fruits and veggies, but far less fiber since the insoluble pulp is removed.

Most juice fasts last for 24-72 hours. Anything longer than 3 days requires medical supervision. During a juice fast you can consume water, herbal tea, broth and nut milks in addition to the fruit/veg juices. Pure juices should ideally be organic and cold pressed to retain nutrients. A typical daily intake might look like:

Time Juice
8 AM 16 oz Green Juice
10 AM 16 oz Fruit Juice
12 PM 16 oz Vegetable Juice
3 PM 16 oz Green Juice
6 PM 16 oz Fruit Juice

Green juices usually contain leafy greens like kale or spinach plus celery, cucumber, lemon and ginger. Fruit juices can be made from any fresh fruits like apples, oranges, berries, melons, etc. Vegetable juices often include carrots, beets, tomatoes and celery.

The Potential Benefits of Juice Fasting

There are several oft-cited benefits of intermittent juice fasting:

May promote weight loss

By cutting way back on calories, juice fasts will generally lead to at least temporary weight loss, especially water weight. Juicing eliminates solid food calories, while providing nutrients to help sustain you. Most juice fasts contain 600-1200 calories per day. The low calorie intake puts your body into a fasted state which can burn stored body fat for energy.

Some research has found juice fasts lasting 3-10 days can result in modest weight loss of 1-5 lbs. Results vary based on calorie intake and activity levels during the cleanse. Any weight lost is usually quickly gained back after resuming normal eating. Longer term studies on juicing and weight loss are limited.

May boost nutrition

Freshly made juices from vegetables and fruits provide concentrated amounts of vitamins, minerals, antioxidants and plant nutrients. Juicing helps ensure you meet nutrient needs on very low calorie intakes. Lots of juice fasts include green juices full of iron, magnesium, potassium, Vitamin C and antioxidants.

However, juice fasting does remove the beneficial insoluble fiber content from whole fruits and veggies. Fiber helps balance blood sugar, lower cholesterol, and promote gut health. Ways to add some fiber back include leaving some pulp in the juices, adding chia seeds, or blending in avocado.

May stimulate detoxification

By abstaining from solid food for several days, advocates claim juice fasting provides the digestive system a rest and allows the body to focus energy on removing accumulated waste and toxins. However the body has its own highly efficient detoxification systems (kidneys, liver, lungs, lymph) that work 24/7. There is little evidence that juice fasting impacts toxin elimination beyond what the body already does.

May reduce inflammation

The natural anti-inflammatory compounds found in fruits, veggies, herbs and spices can help reduce inflammatory markers. Chronic inflammation contributes to many diseases. More research is needed, but juice fasts incorporating potent anti-inflammatory juices could potentially aid inflammatory conditions.

May boost energy and mental clarity

Some juicing fans report feeling more energized and clear headed during short term juice fasts. When you remove heavy processed foods, caffeine, alcohol and refined carbs from your diet, it can lighten the body and elevate mood. Whether these effects persist beyond the juice fast is not well studied.

May improve chronic conditions

Some preliminary evidence suggests juice fasting could aid conditions like asthma, allergies, arthritis, skin conditions, cardiovascular disease and autoimmune disorders. By allowing the GI tract to rest, fasting may help heal the gut lining and reduce food reactions. More research is warranted to confirm benefits.

Potential Drawbacks of Juice Fasting

Despite the touted benefits, juicing comes with some downsides to consider:

Lacks long term weight loss effects

The few pounds shed during a juice fast tend to come right back when you transition back to solid foods. Juice diets provide insufficient calories and protein for most individuals to follow for more than a few days. Doing only juice fasts long term could lead to muscle loss and nutritional deficits. There is no evidence that occasional juice fasting produces sustainable weight loss.

Can cause energy crashes

At first, some people feel energized from the lightened body load and nutrients. But low calories, inadequate protein and lowered blood sugar can lead to mid-fast energy crashes, lightheadedness, headaches, irritability and fatigue for some. Adding protein shakes or nut milks can help stabilize energy.

May worsen diarrhea

The high amounts of natural sugars and lack of fiber in fruit/veg juices can trigger diarrhea, bloating or irritable bowel symptoms in sensitive people. Removing the pulp from produce removes insoluble fiber needed for bowel regularity. Adding some raw greens or psyllium husk powder to juices can help provide fiber.

Can trigger hunger and cravings

All that juicing leaves your stomach mostly empty, which can lead to hunger pangs. Blood sugar spikes and crashes from the high glycemic juices can also increase cravings. Willpower is required to get through the fasting period without snacking. Allowing small snacks like raw nuts, seeds or cut veggies can help ease hunger.

May cause nutrient deficiencies long term

Juice fasts lasting more than a few days provide inadequate protein, fatty acids, iron, zinc, vitamin B12, and other essential nutrients. Extended juicing could lead to nutritional deficiencies if calorie needs are not met. Occasional short term juice fasting is unlikely to cause deficiencies. But pay attention to any symptoms that develop.

Not suitable for some people

Juice fasts are not recommended for pregnant or nursing women, children, diabetics prone to hypoglycemia, underweight individuals, people with eating disorders, or those with kidney problems. Some medications and supplements may also need to be adjusted or avoided. Always consult your doctor before attempting a juice cleanse, especially if you have an underlying medical condition.

Tips for Safe and Successful Juice Fasting

If you do want to give occasional juice fasting a try, keep these safety tips in mind:

– Only fast 1-3 days at first, working up slowly to longer durations if desired
– Drink at least 64 oz of total juices daily
– Include a source of protein like pea protein powder, hemp hearts or a nut milk
– Avoid total calorie intake under 600 calories per day
– Stay well hydrated with water, herbal tea, broth and nut milks
– Get sufficient rest and modify activity levels as needed
– If energized, engage in light exercise like walking, yoga or stretching
– Listen to your body and stop fasting if you feel unwell or exhausted
– Break a fast slowly with broth, raw fruits/veggies before resuming regular diet

Proper preparation and supplies can also help ensure juicing success:

– Get a good juicer that extracts maximum liquid like a slow masticating style
– Have enough fresh organic produce on hand to juice 3-5 times per day
– Wash/prep all produce ahead to streamline juicing
– Use tightly sealed containers to store juices up to 24 hours
– Add lemon juice to prevent oxidation and nutrient loss
– Keep juices chilled to preserve nutrition and taste
– Try adding herbs like mint, basil, parsley to juices for flavor
– Use different fruit/veggie combos to create a variety of flavors

The Bottom Line

Occasional juice fasting lasting 1-3 days appears unlikely to cause harm in most healthy individuals. Short term fasts can provide a nutritional boost and may have some benefits like temporary weight loss, detoxification, reducing inflammation, boosting energy, and resting the digestive tract. But there is limited evidence juice cleanses improve long term health or produce lasting weight loss once normal eating is resumed.

For some people, brief intermittent juice fasting can be a safe way to experiment with calorie restriction and flood the body with antioxidants. But fasting longer than 3-5 days in a row can undermine health over time by causing nutritional deficiencies. Most nutrition experts warn against prolonged juice-only diets.

In the end, consistency is key – the best ‘diet’ is a balanced way of eating you can enjoy and maintain for life. So juice fasting once a week may provide a quick reboot if you have a nutrient-dense whole foods diet the rest of the time. But fasting should not replace eating a well-rounded diet on most days for optimal health.

The Bottom Line

Here are some key takeaways on juice fasting periodically:

– Juice fasts involve only consuming fruit/vegetable juices for 1-3 days
– Potential benefits include weight loss, detoxification, reducing inflammation, resting the gut, and flood of antioxidants
– Downsides include lack of long term weight loss, hunger/cravings, energy crashes, diarrhea, and nutritional deficits long term
– Juice fasts lasting 1-3 days appear relatively safe for most healthy adults
– Consult your doctor before attempting juicing if you have any medical conditions or take medications
– Don’t juice fast more than 3-5 days in a row due to risk of deficiencies
– Proper preparation and supplies can help ensure juicing success
– For lasting health, juice fasting should not replace regular balanced nutrition

In summary, periodic short term juice fasting may offer some benefits, but lacks strong scientific evidence. A whole foods nutrient-dense diet you can follow consistently is ideal for supporting your best lifelong health and weight.