Dairy foods are a big part of the American diet. The United States Department of Agriculture recommends consuming three cups or equivalents daily. Milk and milk foods contain the protein, vitamins and minerals you need to keep your body working at its best. Each nutrient digests differently in your body, so maintaining your weight and eating a balanced diet ensure that dairy foods digest normally in your body.
Dairy Foods
Dairy foods originate from cow's milk and are high-energy, nutrient-dense foods. Butter, cream and whole milk are dairy foods that you should limit due to their high fat and calorie content. Low-fat milk, yogurt, some cheeses and pudding are healthy dairy selections that provide the nutrients you need without excess fat and calories.
Digestion of Macronutrients
Three macronutrients in milk -- fat, protein and carbohydrates -- break down through a series of biological reactions in your digestive tract. Fat sits in your gut the longest since it is a long complex molecule. It undergoes several steps during digestion. Fats must dissolve into fluids in your intestines. Bile acids from your liver break fat into smaller particles. This allows enzymes from your pancreas and intestines to form them into smaller molecules, which become fatty acids or cholesterol. These molecules combine with cells and travel through your bloodstream for storage or absorption. In the first step, acids in your stomach change the structure of protein. Next, pancreatic enzymes in your small intestine break protein strands down further into amino acids, which absorb directly through the intestinal wall. Milk sugar, known as lactose, a type of simple carbohydrate, digests in one simple step. An enzyme in your small intestine changes lactose into an absorbable sugar that goes directly into your bloodstream.
Digestion of Micronutrients
Micronutrients, such as vitamins and minerals, absorb directly into your bloodstream through the walls of the small intestine. Dairy foods are the primary source of calcium in the diet of Americans. Milk and dairy foods provide vitamin D, a type of fat-soluble vitamin your body uses to absorb calcium, keeping bones and teeth strong. Fat-soluble vitamins stay in your liver or fatty tissues until you need them. Dairy foods also have a mineral called potassium that functions by maintaining your blood pressure. Since all of these nutrients absorb through your intestinal walls, having some sort of intestinal disorder, such as irritable bowel syndrome or diverticulitis, may affect digestion and absorption.
Digestion Problems
Lactose intolerance affects your ability to break down lactose in milk and dairy foods. Lactose intolerance means that your body does not have lactase, or might have poorly functioning lactase, an enzyme necessary for breaking down lactose. While this condition is not serious, it may lead to gas, bloating, cramping or diarrhea shortly after consuming foods containing lactose. There is no treatment for lactose intolerance, explains the Food and Drug Administration. Once you have a diagnosis, the best way to manage symptoms is to eliminate dairy foods from your diet. There are a few over-the-counter supplements you can take that act like lactase, helping the digestion of lactose, but check with your doctor ahead of time to see if you are healthy enough for these types of supplements.
