Fructose Malabsorption: This condition is characterized by the inability of the small intestine to absorb fructose, a common sugar found in many carbohydrates. Symptoms include severe nausea, bloating, and abdominal pain after consuming fructose-containing foods, making it a highly plausible diagnosis given the patient's symptoms.

Lactose Intolerance: A condition where the body is unable to digest lactose, a sugar found in milk and other dairy products, due to a deficiency of the enzyme lactase. Symptoms can include nausea, bloating, and gas after consuming lactose-containing carbohydrates.
Small Intestine Bacterial Overgrowth (SIBO): A condition where there is an abnormal increase in the bacteria that inhabit the small intestine. Consuming carbohydrates can exacerbate symptoms of SIBO, including bloating, nausea, and abdominal pain.
Irritable Bowel Syndrome (IBS): A gastrointestinal disorder characterized by chronic abdominal pain, bloating, and alteration of bowel habits. While the exact cause of IBS is unknown, carbohydrate consumption can trigger or worsen symptoms in some individuals.

Celiac Disease: An autoimmune disorder where the ingestion of gluten leads to damage in the small intestine. It can cause severe nausea, bloating, and other gastrointestinal symptoms after consuming gluten-containing carbohydrates. Missing this diagnosis could lead to long-term health complications, including malnutrition and increased risk of other autoimmune diseases.
Gastric Cancer: Although rare, gastric cancer can present with nonspecific symptoms such as nausea and bloating, especially after eating. It is crucial to consider this diagnosis to ensure timely intervention and treatment.
Pancreatic Insufficiency: A condition where the pancreas does not produce enough digestive enzymes, leading to malabsorption of nutrients, including carbohydrates. This can result in severe gastrointestinal symptoms and requires prompt diagnosis and treatment to prevent malnutrition and other complications.

Sucrose Isomaltase Deficiency: A rare genetic disorder that affects the body's ability to digest sucrose and other sugars. Symptoms can include severe nausea, bloating, and abdominal pain after consuming sucrose-containing foods.
Glucose-Galactose Malabsorption: A rare condition where the body is unable to absorb glucose and galactose, two simple sugars. This can lead to severe gastrointestinal symptoms, including nausea and bloating, after consuming carbohydrates that contain these sugars.