Causes of Weakness in Legs. Weakness in the legs can be caused by many conditions and diseases. Weakness means there is less strength in the muscles than there should be. Some people mistake fatigue as weakness, but technically in the medical world, they aren't the same. People with the flu or cancer, for example, may say they feel weak when they're referring to sluggishness.
1 (Outside of the body, Lactobacillus acidophilus is the probiotic that is found in some yogurts.). 2  Foods that contain probiotics include: some juices and soy drinks, fermented and unfermented milk, buttermilk, some soft cheeses, miso, tempeh, kefir, kim chi, sauerkraut, and many pickles.
Probiotics are found in foods such as yogurt, while prebiotics are found in whole grains, bananas, onions, garlic, honey and artichokes. In addition, probiotics and prebiotics are added to some foods and available as dietary supplements.