Keto diets have become increasingly popular in recent years as a way to lose weight and improve health. Some people wonder if following a juice diet can also be considered keto. This article will examine what keto and juice diets entail, their similarities and differences, and whether it’s possible or advisable to combine the two.
What is a Keto Diet?
A ketogenic or “keto” diet is a very low-carb, high-fat diet. The goal is to reach ketosis, a metabolic state where your body burns fat for fuel instead of carbs. This happens when carb intake is restricted to around 50 grams per day or less. When carbs are severely reduced, your body begins burning fat for energy instead of carbs through a process called ketosis.
On a keto diet, up to 80% of daily calories come from fat. Protein makes up around 20% of calories, while carbs are restricted to only 5-10% of total calories.
Reaching and staying in ketosis requires carefully restricting carb sources like grains, starchy vegetables, fruit, sugars, and all highly processed foods. Keto-friendly foods include:
- Meat
- Fish and seafood
- Eggs
- Full-fat dairy
- Nuts and seeds
- Non-starchy vegetables like leafy greens, broccoli, zucchini
- Avocado and olive oil
- Some berries in moderation
People may choose to follow a keto diet to help:
- Lose weight
- Reduce seizures in epilepsy (the original medical use)
- Manage type 2 diabetes
- Improve polycystic ovary syndrome (PCOS)
- Potentially aid other brain disorders like Alzheimer’s
What is a Juice Diet?
A juice diet involves getting most or all of your daily calories from pressed vegetable and fruit juices instead of solid foods. Sometimes juice fasts or detoxes last for only a few days, while some people may follow juice-focused regimens for weeks at a time.
On a juice diet, solid foods are eliminated or significantly restricted. Some popular choices for juice diets include:
- Fruit and vegetable juice blends
- Green juices like kale, spinach, cucumber
- Root juice like carrot, beet, ginger
- Citrus juice such as orange, grapefruit, lemon
- Some allow small amounts of protein powder or nut milks
Proponents of juice diets claim benefits like:
- Fast weight loss
- Toxin removal or body cleansing
- Increased vegetable and fruit intake
- Reduced calories compared to normal diet
- More energy
- Improved skin appearance
- Better digestion and regularity
Differences Between the Diets
Keto and juice diets have very different macronutrient ratios and allowed foods.
| Nutrient | Keto diet | Juice diet |
|---|---|---|
| Fat | Very high fat, around 70-80% of calories | Very low fat |
| Protein | Moderate protein, around 20% of calories | Low to moderate protein |
| Carbs | Very low carbs, around 5% of calories | High carbs from fruit/veggie juices |
The keto diet relies on fat as the main calorie and energy source. Protein makes up the second largest macro, with very strict limits on carbohydrates. In contrast, juice diets are extremely low in fat, moderate to low in protein, and very high in carbs from the fruit and vegetable juices.
These diets also differ significantly in allowed foods:
| Foods | Keto diet | Juice diet |
|---|---|---|
| Meat, eggs, fish | Allowed | Not allowed |
| Dairy products | Allowed, especially high fat like cheese, butter, cream | Not allowed |
| Nuts & seeds | Allowed in moderation | Not allowed |
| Non-starchy vegetables | Allowed | Juices allowed, but not whole vegetables |
| Fruits | Only berries in small portions | Fruit juices allowed |
| Grains | Not allowed | Not allowed |
| Beans & legumes | Not allowed | Not allowed |
| Processed foods, sweets | Not allowed | Not allowed |
As shown above, the keto diet includes sources of fat and protein like meat, fish, eggs, dairy, nuts that are restricted on juice diets. Juice diets also eliminate whole vegetables and natural fats.
Can You Do a Juice Diet and Stay in Ketosis?
It would be very challenging to follow a juice diet and remain in ketosis, because of the high carb content of the juices. To stay in ketosis, carb intake needs to be restricted to around 50 grams or less per day.
Fruit and vegetable juices are naturally high in carbs. Around 8 ounces of vegetable juice can contain 15-30 grams of carbs. An 8 ounce glass of fruit juice like orange juice has over 20 grams of carbs.
If juices make up most of your daily food intake, it would be nearly impossible to keep net carbs low enough to maintain ketosis.
You would need to severely limit juice intake and carefully choose very low sugar vegetables like celery, spinach, cucumbers and drink them in very small portions. Even then, staying in ketosis long term would be extremely difficult. You would also miss out on the fat and protein provided by whole foods allowed on keto.
Advantages of a Juice Diet
Despite the inability to reach or sustain ketosis, juice diets may offer some benefits depending on the specific protocol followed:
- Nutrition – Juices can provide concentrated amounts of vitamins, minerals, and plant compounds from vegetables and fruits.
- Low calorie – Juice diets tend to be lower in calories than normal diets, which can lead to short-term weight loss.
- Blood sugar control – The fiber in vegetable juices may moderate blood sugar spikes from the fruit juices.
- Detoxification – Some juice diets claim to detoxify the body, but evidence is lacking.
- Compliance – Juice diets may be easier to comply with short term compared to restrictions of keto diets.
Potential Downsides of Juice-Only Diets
There are also many drawbacks to juice-focused diets to keep in mind:
- Nutrient deficiencies – Juice diets lack protein and essential fatty acids. Longer term restrictions could lead to deficiencies in vitamins and minerals.
- Loss of muscle and lean mass – The low protein doesn’t support building or maintaining muscle.
- Slow metabolism – Severe calorie deficits can slow the metabolism.
- Loss of electrolytes – Rapid water weight loss depletes important electrolytes like sodium, potassium, and magnesium.
- Lack of gut-supporting fiber – The removed pulp loses a lot of fiber and compounds that feed healthy gut bacteria.
- Hunger and low energy – The limited calories and nutrition lead to hunger, fatigue, and inability to focus.
- Weight re-gain – Juice diets typically lead to fast weight loss, but the results are rarely sustainable long term.
Sample 1-Day Juice Diet
Here is an example of what a day on a juice diet might look like:
| Time | Juice |
|---|---|
| 8 am | 16 oz lemon water |
| 10 am | 12 oz green juice (kale, cucumber, celery, parsley, ginger, lemon) |
| 12 pm | 12 oz carrot apple turmeric juice |
| 2 pm | 12 oz sweet potato, carrot, orange juice |
| 4 pm | 12 oz beet, carrot, pineapple juice |
| 6 pm | 12 oz tomato, spinach, avocado juice |
This provides around 1600 calories per day, high in carbs from the fruit and vegetable juices. Protein and fat intake are minimal with this juice-focused plan.
Should You Try a Juice Diet?
A juice diet can be an effective short-term strategy for quick weight loss or as a way to increase produce intake. However, juice diets are difficult to sustain more than several weeks due to potential nutrient deficiencies and hunger.
For some people, a juice diet may be a good way to kick start a healthier diet and lifestyle. But most nutrition experts warn against following strict juice fasts or detoxes for more than 3-5 days at a time.
Juice diets are not compatible with a keto diet or nutritional ketosis. The high carb content from the juices makes it impossible to reach or sustain ketosis.
Someone looking to go keto should not attempt a full juice diet. However, adding a fresh vegetable juice a few times a week could provide extra nutrients.
As with any restrictive diet, speak with your healthcare provider before attempting a juice fast, especially if you have any underlying medical conditions.
The Bottom Line
A juice diet is very high in carbohydrates from the vegetable and fruit juices so it is incompatible with ketogenic diets. While juice fasts may have some benefits in the short-term, they lack protein, fat, and other nutrients essential for long-term health. For those wanting to follow a keto diet, whole foods focused on natural fats, proteins, and low carb vegetables will be necessary to reach and sustain ketosis.
