When you think about energy and metabolism, you might picture a strong cup of coffee or a high-intensity workout. But your body’s real “energy engines” run on something smaller: B vitamins. These essential nutrients don’t provide energy like carbs or protein, but they’re critical for turning the food you eat into fuel for your cells.1 For patients on a weight loss journey—especially those who have had bariatric surgery or are taking GLP-1 medications—B vitamins can make the difference between a steady, energized day and one marked by fatigue and sluggishness.* Meet the B Vitamin Family B vitamins work together as a team, but each has a unique role in energy metabolism, nervous system health, and overall wellness. B1 (thiamine) Helps convert carbohydrates into energy, supports nerve function, and aids muscle contraction Why it matters: Deficiency can cause fatigue, muscle weakness, and nerve damage, particularly in post-bariatric patients. B2 (riboflavin) Helps break down fats, proteins, and carbs for energy while supporting antioxidant activity Why it matters: Without it, your body can’t efficiently release energy from food. B3 (niacin) Powers more than 400 enzymatic reactions involved in energy production, cholesterol metabolism, and DNA repair Why it matters: Low niacin levels can reduce stamina and metabolic efficiency. B5 (pantothenic acid) Known as the “anti-stress vitamin,” it produces coenzyme A, essential for the Krebs cycle (your main energy pathway). Why it matters: Without it, your ability to burn fat for fuel decreases. B6 (pyridoxine) Helps your body release glucose from stored glycogen and supports amino acid metabolism Why it matters: Helps stabilize blood sugar for steady energy and appetite control. B7 (biotin) Supports the breakdown of carbs, fats, and proteins while promoting healthy hair, skin, and nails Why it matters: Deficiency can slow fat metabolism and cause brittle nails or hair loss—common during rapid weight loss. B9 (folate) Needed for DNA synthesis, cell division, and red blood cell formation Why it matters: Low folate leads to fatigue, anemia, and slower recovery. B12 (cobalamin) Vital for nerve health, red blood cell production, and fatty acid metabolism Why it matters: One of the most common deficiencies after bariatric surgery, low B12 can affect energy, focus, and mood.1 Why B Vitamins Are Critical to Weight Loss Success Patients on a weight loss journey, especially those with highly restricted diets, are at higher risk of B vitamin deficiencies. Here’s why: Reduced intake: Smaller meals mean less total nutrient consumption. Absorption challenges: Bariatric procedures alter parts of the digestive tract where B vitamins are absorbed. Increased demand: Rapid weight loss and healing require extra metabolic support. Without enough B vitamins, patients may experience fatigue, weakness, nerve issues, slower metabolism, and weight loss plateaus. Foods Source of B Vitamins While supplements are required after bariatric surgery and with popular medical weight loss therapies, high-quality, nutrient-dense food sources are important too. Here’s where to find B vitamins in food:1 B1 (thiamine): Pork, sunflower seeds, fortified cereals B2 (riboflavin): Eggs, dairy products, almonds, spinach B3 (niacin): Chicken, turkey, tuna, mushrooms B5 (pantothenic acid): Avocados, sweet potatoes, mushrooms B6 (pyridoxine): Salmon, chickpeas, bananas B7 (biotin): Eggs, salmon, nuts, seeds B9 (folate): Dark leafy greens, lentils, asparagus B12 (cobalamin): Clams, beef, fish, dairy products Tip: Cooking and processing can destroy some B vitamins, so include fresh or minimally processed foods whenever possible. Supplement Tips for Weight Loss For most patients, diet alone isn’t enough to meet B vitamin needs. Here’s how to get what your body needs: Choose a high-quality bariatric multivitamin that follows ASMBS guidelines and includes all 8 B vitamins in bioavailable forms. Consider additional B12 supplementation (often sublingual or injectable) if recommended by your healthcare practitioner Look for methylated forms of B12 (methylcobalamin) and folate (methylfolate) for better absorption. Take supplements consistently. B vitamins are water-soluble, so your body needs them daily. Surprising Facts About B Vitamins They’re water-soluble—your body doesn’t store most of them (except B12) They can affect mood and mental clarity—several B complex vitamins (B6, B9, B12) are involved in neurotransmitter production1 Some are easily destroyed—cooking, processing, and even light exposure can reduce B vitamin levels in food Deficiency symptoms can mimic other issues—fatigue, irritability, or brain fog may not be from lack of sleep but could indicate low B vitamin levels.1 The Bottom Line For anyone on a bariatric or medical weight loss journey, B vitamins are essential. They: Convert food into energy Keep metabolism running smoothly Support nerve and brain health Prevent fatigue that can derail progress Be sure to take a high-quality bariatric multivitamin with B vitamins to fill nutrient gaps, maintain your energy, and support long-term weight loss success. Shop B Vitamins Now References 1. Hanna M et al. Perm J. 2022;26(2):89-97.