Don't switch to toddler formula. It's totally unnecessary and just a ploy to get more money for the formula companies:( ESPECIALLY if you're going to continue breastfeeding!
We are the only species that weans from our own milk to another species' milk. When you look at it that way, you see it's a little odd and probably not needed with a balanced diet. Have you tried yogurt and cheese? They are usually tolerated better because for most, it's not an allergy, it's a protein issue. The proteins are broken down during fermentation and processing of dairy products (ice cream doesn't count, it's just frozen).
Really, soy isn't great. It's horribly over-processed and high in estrogens. Almond milk is a great alternative because it's naturally high in protein and calcium. Goat milk is also a good alternative. It's the closest there is to human milk when you look at the proteins, so many children who don't tolerate cow's milk can have goat's milk.
But, don't worry about supplementing too much if you are happy to continue breastfeeding. Here's info on the nutrition of breastmilk in the second year:
In the second year (12-23 months), 448 mL (15oz) of breastmilk provides:
* 29% of energy requirements
* 43% of protein requirements
* 36% of calcium requirements
* 75% of vitamin A requirements
* 76% of folate requirements
* 94% of vitamin B12 requirements
* 60% of vitamin C requirements
And here is info about places to get needed nutrients instead of milk:
There is no need to add cow's milk to your toddler's diet (or the equivalent nutrients from other milks or foods) as long as your baby is nursing at least 3-4 times per day. Cow's milk is really just a convenient source of calcium, protein, fats, vitamin D, etc. - it's not required. There are many people in many parts of the world who do not drink milk and still manage to get all the calcium, protein, fats, vitamin D, etc. that they need.
* Good non-dairy sources of protein include meats, fish, peas & beans (chick peas, lentils, baked beans, etc.), tofu and other soy products, boiled eggs, peanut and other nut butters (if your child is not allergic).
* Good non-dairy sources of fats include soy and safflower oils, flax seed and flax seed oil, walnuts, fish and fish oils, avocado. Adding fats to cooking and baking can work well, for example, stir fry in safflower oil or make mini-muffins with soy or rice milk, oil or butter, and eggs.
* Calcium may be derived from many nondairy sources.
* Vitamin D can be supplied by sunlight exposure and food sources.
* If your child is not nursing regularly and is not allergic to cow's milk products, but simply doesn't like cow's milk, you can incorporate milk into your child's diet in other ways. Many children like cheese, whole-fat yogurt or ice cream. You can also put milk into various food products: pancakes, waffles, muffins, French toast, scrambled eggs, mashed potatoes, and baked goods.
* Some moms wish to offer cow's milk to their toddler, but baby doesn't like it. Over the age of 12 months, milk becomes a more minor part of a child's diet. It is sometimes helpful to mix increasing amounts of cow's milk with your expressed milk to help baby get used to the taste. Many dietitians see nothing wrong with adding some flavor (such as strawberry or chocolate) to cow's milk.