Vegetables and fruits are typically low in calories and filled with essential nutrients, making them an essential part of any healthy diet. Getting more of these nutritious foods may help lower your risk for heart disease, high blood pressure, digestive problems, vision problems and cancer. They don't supply all of the essential nutrients, however, so it isn't a good idea to eat only fruits and vegetables for any significant amount of time. Check with your doctor before attempting such a diet to make sure it would be safe for you. Although a two-week all fruit and vegetable diet might not result in long-term consequences, the longer you follow this type of diet, the more likely you'll be to experience nutrient deficiencies.
Calorie Considerations for a Two-Week Fruit & Veggie Diet
A diet consisting of just fruits and vegetables is probably going to be low in calories overall. Diets that are too low in calories, including those under 1,200 calories per day for women and those under 1,800 calories per day for men, can slow your metabolism and if followed long-term, can increase your risk for heart problems, osteoporosis and other health conditions. If you're interested in trying this type of diet to lose weight, keep in mind that a slower metabolism also makes weight loss more difficult. Not getting enough calories can also cause headaches, dizziness, fatigue, emotional issues and fainting.
Increased Fiber From Fruits and Vegetables
Fruits and vegetables are among the best sources of fiber, so if you only eat these foods, you're probably going to be greatly increasing your dietary fiber. If you make a sudden switch from your regular diet to one consisting of just fruits and vegetables, the sudden increase in fiber will be difficult for your body to handle and may leave you suffering from diarrhea and gas. It's better to gradually increase your fiber intake. Be sure to drink plenty of water on this type of diet, as this will help minimize the gas and constipation caused by the higher amounts of fiber it contains. Very high amounts of fiber can also interfere with the absorption of some nutrients and interact with certain medications, so check with your doctor before suddenly adding a lot more fiber to your diet.
Potential Long-Term Consequences
Don't follow a fruit-and-vegetable-only diet for a long time. While a two-week diet of this type isn't likely to cause serious deficiency symptoms, fruits and vegetables don't contain significant amounts of protein, essential omega-3 and omega-6 fats, vitamin D, B-vitamins, zinc, iron, calcium, chromium, copper, iodine, manganese, molybdenum, phosphorus or selenium. You need to get enough of the essential fats to maintain proper brain, eye and skin health and keep your hormones at the proper levels.
Not getting enough protein, even for a short time, can have serious consequences. A protein deficiency may cause muscle loss, make it harder for wounds to heal and make you more likely to get sick. It may also trigger mental confusion, digestive issues and skin and hair problems. Other nutrient deficiencies from an all-vegetable diet can affect you skin, hair, bones, hormone levels and blood.
A Well-Balanced Diet
A diet of fruits and vegetables alone is too restrictive to provide all of the nutrients you need, but if you're wanting to avoid animal proteins, it's possible to get these nutrients from a well-planned vegetarian or vegan diet. Depending on the exact content of your diet, you might require vitamin B-12 supplements and perhaps vitamin D supplements as well, depending on where you live and how much time you spend in the sun. Eating eggs and dairy products, as some vegetarians do, would add complete protein and seafood would provide protein as well as omega-3 fats.
No matter what diet you follow, fruits and vegetables are an important source of vitamins, minerals, fiber and plant phytochemicals. The USDA recommends adults consume 1 1/2 to 2 cups of fruit per day and 2 to 3 cups of vegetables each day for good health.
- Harvard School of Public Health: Vegetables and Fruits
- FamilyDoctor.org: Vegetarian Diet: How to Get the Nutrients You Need
- Colorado State University Extension: Dietary Fiber
- U.S. Department of Agriculture: Dietary Reference Intakes (DRIs): Elements
- U.S. Department of Agriculture: Dietary Reference Intakes (DRIs): Vitamins
- University of Kentucky Cooperative Extension: Fad Diets
- American College of Sports Medicine: Metabolism Is Modifiable With the Right Lifestyle Changes
- CNN: What's the Danger of an All-Fruit Diet?
- Merck Manuals: Essential Fatty Acid Deficiency
- UT San Diego: Protein Deficiency Is Cause for Concern, Especially in Elderly