The minute you announce your pregnancy, well-meaning friends and family have plenty of advice on how you should be "eating for two." But this isn't entirely true. When you're pregnant, your body, quite efficiently, absorbs nutrition extremely well. So what you should really do is to eat healthy, and not twice as much. During the first trimester, there is no substantial reason to increase the intake of calories and proteins because there is no significant gain in size of foetus.
What Should I Include In My Diet In The First Trimester?
There are some key nutrients that the body requires during the first trimester.
Folic Acid:;is required for the development of nervous system, blood formation and it also has a positive effect on birth weight of infants. You can get your dose of folic acid by including wheat germ, pulses, nuts, green leafy vegetables especially spinach, oranges, fresh beans in your diet.

Iron-rich foods:;are necessary for foetal growth, expansion of mother's tissues and for the growing volume of blood which in turn supply nutrients to the foetus. For non-vegetarians organ meats and eggs help in providing iron. For vegetarians, iron-rich foods such as dark green leafy vegetables, such as mustard greens, chulai, mint, methi, and bathua are good sources of iron. Other sources include soybeans, lobia, lentils, whole wheat dalia, riceflakes and fruits such as watermelon, raisins and nuts like pistachio. If you eat foods that contain vitamin C at the same time as these foods, it will help your body to absorb the iron from the meal. You could have a glass of Vitamin C rich fruit juice with your meal
Vitamin B6 (pyridoxine);helps tackle nausea, a common problem faced in pregnancy. Eating wholegrains, especially cereals and legumes, wheat bran, wheat germ, dried yeast, nuts, seeds, leafy vegetables, and meat and egg helps in meeting your B6 requirements
Water and fluids;Pregnancy doesn't change your daily requirement of 8-10 glasses of water per day. In addition to this, make sure you include some healthy drinks like tender coconut water, buttermilk and fresh fruit juice, to always stay hydrated.