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Do You Feel Weak After Losing Weight?

author image Allison Stevens
Writing since 1978, Allison Stevens was writer and publisher of the Calvary Christian Fellowship newsletter and has had work appear in various online publications. Stevens has certification to teach group fitness and is a licensed Zumba instructor, teaching fitness classes for adults and children daily. She enjoys researching various subjects including health, and holds an Associate of Arts.
Do You Feel Weak After Losing Weight?
Dieting may cause weakness for several reasons. Photo Credit: Purestock/Purestock/Getty Images

If you have cut calories and added exercise to your routine, you should feel healthy and energized but sometimes you don't. The early stages of a diet can especially pose problems for your energy level. Your body is undergoing a period of stress and adaptation, which may leave you feeling less than perky.

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Ketosis can cause headaches and nausea.
Ketosis can cause headaches and nausea. Photo Credit: LarsZahnerPhotography/iStock/Getty Images

Fad diets that restrict carbohydrate intake and encourage high protein consumption puts your body at risk for ketosis. Your body normally burns carbohydrates first, but when you seriously reduce starch from your eating plan, your body turns to its next energy source, fat. Ketosis is known to cause dull headaches, nausea, vomiting, pain in the abdomen, accelerated breathing and heart problems, in addition to fatigue and weakness, according to Vanderbilt University. Avoid the weakness ketosis causes by eating a balanced diet including whole grains, fruits and vegetables.


Dehydration may be causing your weakness.
Dehydration may be causing your weakness. Photo Credit: Wavebreakmedia Ltd/Wavebreak Media/Getty Images

Another possible cause for your lack of energy during weight loss is dehydration, which results when your body sheds more liquid than it takes in. Avoid using diuretics or laxatives to aid your weight-loss attempts, as losing water does not produce fat loss. Also, if you have started exercising, be sure to compensate the water lost from sweat by drinking plenty of water. In addition to fatigue, dehydration may make you feel dizzy or lightheaded and your urine may appear darker than usual. Avoid dehydration by drinking plenty of fluids, especially zero-calorie water.


Your weakness could be caused by anemia.
Your weakness could be caused by anemia. Photo Credit: sugar0607/iStock/Getty Images

If you have lost weight through restricting the amount of protein you are ingesting, your weakness may be caused by anemia due to iron-deficiency. The symptoms of iron-deficient anemia include poor memory, shortness of breath, hair loss, dizziness and fatigue. You may also experience a feeling of cold extremities. Decrease your risk of anemia by eating iron-rich foods such as meat, eggs, beets, spinach, lettuce, almonds, soybeans, bananas, plums, strawberries, carrots and tomatoes.


Loss of the mineral potassium may be another reason you're feeling weak while dieting.
Loss of the mineral potassium may be another reason you're feeling weak while dieting. Photo Credit: moodboard/moodboard/Getty Images

Loss of the mineral potassium may be another reason you're feeling weak while dieting. Potassium may be lost from use of diuretics, physical or mental stress or consuming alcohol, sugar or coffee. Potassium may also be lost by long-term vomiting as with anorexia or bulimia. In addition to weakness, low potassium may cause bloating, cramping and abdominal pain. Avoid potassium loss by eating foods such as raisin bran cereal, carrots, plums, oranges, tomatoes, spinach, acorn squash, almonds and lima beans -- all diet-friendly foods.

Improper Nutrition

Stop severe dieting.
Stop severe dieting. Photo Credit: Warren Goldswain/iStock/Getty Images

Drastic calorie reduction and inadequate nutritional balance may also be to blame for your feeling weak or tired. Stop severe diet plans designed for rapid weight loss after one week and follow that with at least two weeks of balanced eating to guarantee proper nutrition. If you return to a more normal diet and still feel weak or fatigued, consult your physician. Speak with your doctor prior to starting a new eating plan, as well.

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