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Orders are prepared in 1–3 business days and arrive 3–7 business days after they ship. Alaska, Hawaii, Puerto Rico, U.S. territories and APO/FPO/DPO addresses can take longer. You get a tracking number by email as soon as your order ships.
Free returns within 30 days of delivery: we email you a prepaid return label, no reason needed. Items must be unopened, with the manufacturer or tamper-evident seal intact, in their original packaging. Opened, used or partially consumed vitamins, minerals and supplements, items with broken or missing seals, and gift cards can't be returned. Damaged, defective, incorrect or expired items are always covered. Refunds go back to your original payment method within 10 business days of approval.
If you have a question about an item, its label or your order, email sales@naturalvitaminsonline.com with the product name or order number. We answer every message by email and reply within 1 business day (Monday to Friday, Eastern Time).
Talk to your doctor or pharmacist before starting a supplement, especially if you're pregnant or nursing, take medication, or have a medical condition.
†These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease.
Talk to your doctor or pharmacist before starting a supplement, especially if you're pregnant or nursing, take medication, or have a medical condition.
Optimum Nutrition Serious Mass is a chocolate weight-gainer powder designed to help increase daily calorie intake, providing over 1,200 calories and 50 g of blended protein per 2-scoop serving.
Serious Mass is made for people aiming to raise their calorie intake during a bulking phase or while working toward weight gain and size goals. It is intended to supplement normal food intake, rather than replace the role of a regular diet. The brand positions it for use alongside regular resistance training over time; results are not guaranteed.
A 2-scoop serving provides over 1,200 calories, 50 g of blended protein and over 249 g of carbohydrates. The protein blend is intended to support muscle repair, recovery and lean mass development after intense training, while the carbohydrates provide energy and support glycogen replenishment.
Blend the powder with milk, fruit, peanut butter, nuts or other calorie-dense ingredients to tailor the shake. These additions can increase its calorie content and let you adjust the flavor and ingredients to suit your routine.
Serious Mass is intended for people who want support increasing calorie intake for weight gain, a bulking phase or size and strength goals. Its formulation also includes more than 20 vitamins and minerals, including vitamin C and zinc, to contribute to daily nutritional intake.
Optimum Nutrition Serious Mass is suited to active people who need a convenient way to add calories and protein around meals and training. It is a chocolate powder for a calorie-increasing routine, with a 2-scoop serving designed to complement normal food intake and regular resistance training.
Maltodextrin, Proprietary Protein Blend (Whey Protein Concentrate, Calcium Caseinate, Egg Albumen, Sweet Dairy Whey), Cocoa, Natural and Artificial Flavor, Vitamin and Mineral Blend (Dipotassium Phosphate, Magnesium Aspartate, Dicalcium Phosphate, Calcium Citrate, Ascorbic Acid, Niacinamide, Zinc Citrate, Beta Carotene, D-calcium Pantothenate, D-alpha Tocopheryl Succinate, Selenomethionine, Copper Gluconate, Ferrous Fumarate, Manganese Amino Acids Chelate, Thiamin Mononitrate, Pyridoxine Hydrochloride, Riboflavin, Chromium Polynicotinate, Folic Acid, Biotin, Molybdenum Amino Acid Chelate, Cholecalciferol, Potassium Iodide, Cyanocobalamin), Acesulfame Potassium, Medium Chain Triglycerides.
Q: What does one serving of Optimum Nutrition Serious Mass provide?
A: One 2-scoop serving of Optimum Nutrition Serious Mass provides over 1,200 calories, 50 g of blended protein and over 249 g of carbohydrates.
Q: How can I use Optimum Nutrition Serious Mass?
A: Blend Optimum Nutrition Serious Mass with milk, fruit, peanut butter or nuts, and use it after a workout or between meals alongside normal food intake.
Free standard shipping on every order to U.S. addresses, with no minimum. Orders are prepared in 1–3 business days and arrive 3–7 business days after they ship. Alaska, Hawaii, Puerto Rico, U.S. territories and APO/FPO/DPO addresses can take longer. You get a tracking number by email as soon as your order ships. See shipping details.
Free returns within 30 days of delivery. Free returns within 30 days of delivery: we email you a prepaid return label, no reason needed. Items must be unopened, with the manufacturer or tamper-evident seal intact, in their original packaging. Opened, used or partially consumed vitamins, minerals and supplements, items with broken or missing seals, and gift cards can't be returned. Damaged, defective, incorrect or expired items are always covered. Refunds go back to your original payment method within 10 business days of approval. See returns & refunds.
Damaged, defective, incorrect or expired item? Email your order number, a photo and the lot/expiration details to sales@naturalvitaminsonline.com and we will arrange a replacement or refund; this is always covered. Please report visible shipping damage within 7 days of delivery.
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