Too much Vitamin D can lead to toxicity with symptoms like low appetite, irregular bowel movements, lethargy, and a higher cancer risk. Experts advise against taking 60,000 IU daily for months. The recommended daily allowance for most adults is 600 IU. Too much Vitamin D can lead to toxicity with symptoms like low appetite, irregular bowel movements, lethargy, and a higher cancer risk. Experts advise against taking 60,000 IU daily for months. The recommended daily allowance for most adults is 600 IU. Health and Fitness, Health Tips, Exercises & Workout Tips, Diet & Wellness | Times of India Lifestyle