Structured Nutritional Data & Citations
Nutritional Profile: Tea (Camellia sinensis) - Brewed, Unsweetened
This section details the nutritional content and physical properties of plain brewed tea, derived from Camellia sinensis leaves, without any added milk, sugar, or flavorings.
Macronutrients and Calories
| Component | Per 100g (Brewed Liquid) | Per Standard Serving (1 cup, ~240g Brewed Liquid) | Reference (FDC ID) |
|---|---|---|---|
| Energy | 1 kcal | 2 kcal | 171444 |
| Protein | 0.1 g | 0.2 g | 171444 |
| Total Fat | 0.0 g | 0.0 g | 171444 |
| Carbohydrates | 0.3 g | 0.7 g | 171444 |
| - Sugars | 0.0 g | 0.0 g | 171444 |
| - Fiber | 0.0 g | 0.0 g | 171444 |
Note: Data for 'Tea, black, brewed' from USDA FoodData Central is representative of most plain brewed teas, though minor variations exist between types (e.g., green, white, oolong) and steeping methods.
Key Micronutrients
Vitamins
- Water-soluble Vitamins: Generally negligible amounts. Trace levels of some B vitamins (e.g., Folate) might be present but not nutritionally significant in typical serving sizes.
- Fat-soluble Vitamins: Absent.
Minerals
- Fluoride: ~0.1-0.4 mg per 240g serving (varies significantly by soil, tea type, and brewing).
- Manganese: ~0.1-0.2 mg per 240g serving.
- Potassium: ~20-30 mg per 240g serving.
- Trace Minerals: Very small amounts of Magnesium, Calcium, Zinc, and Copper may be present.
Antioxidants & Bioactive Compounds
Tea is particularly rich in polyphenols, which act as powerful antioxidants. The specific compounds and concentrations vary by tea type:
- Flavonoids:
- Catechins: Predominant in green tea (e.g., Epigallocatechin Gallate - EGCG, Epicatechin - EC, Epigallocatechin - EGC).
- Theaflavins & Thearubigins: Formed during the oxidation (fermentation) of black tea. Responsible for black tea's characteristic color and flavor.
- L-Theanine: An amino acid unique to tea, known for its calming and focus-enhancing effects.
- Caffeine:
- Black Tea: ~30-70 mg per 240g serving.
- Green Tea: ~20-45 mg per 240g serving.
- White Tea: ~15-30 mg per 240g serving.
- Oolong Tea: ~30-50 mg per 240g serving.
- (Decaffeinated tea significantly reduces caffeine content.)
Functional Impact
- Glycemic Index (GI): Very low (effectively 0) for unsweetened brewed tea.
- Glycemic Load (GL): Very low (effectively 0) for unsweetened brewed tea.
- Satiety Score: Low. While the volume of liquid can temporarily contribute to fullness, unsweetened tea provides minimal caloric density or macronutrient content to induce sustained satiety. Its main functional impact is hydration and stimulant effects (caffeine) or relaxation (L-Theanine).
Physical Properties
- Density (Brewed Liquid): ~1.00 - 1.005 g/cm³ at 20°C. Very close to the density of pure water, with slight variations depending on the concentration of extracted solids.
- Volumetric Contraction After Brewing ("Cooking"): For the liquid phase, volumetric contraction is negligible (<0.1%) after the brewing process. The primary change is the extraction of soluble solids into the water, which slightly increases the liquid's density but does not significantly reduce its volume. The dry leaves themselves, however, absorb water and expand significantly during brewing.
Citations & References
- USDA FoodData Central. (n.d.). FoodData Central, FDC ID: 540031, Tea, black, brewed. Retrieved from https://fdc.nal.usda.gov/fdc-app.html#/food-details/540031/nutrients
- USDA FoodData Central. (n.d.). Search for other tea types (e.g., green tea, oolong tea) for comparative data.
- Scientific Consensus on Bioactive Compounds in Tea: Reviewed across multiple studies, including those published in Journal of Agricultural and Food Chemistry, Critical Reviews in Food Science and Nutrition, and Phytomedicine. These sources collectively affirm the presence and health implications of flavonoids, L-theanine, and caffeine in various tea preparations.
Field Notes: Dr. Aria Vance
Subject: Tea
Focus: Volumetric expansion/contraction, historical context, tracking challenges.
The Manual Tracking Problem with Tea
Dr. Aria Vance, Lead Nutrition Data Scientist, NutriSnap.
Date: 2024-04-29
Tea. Ah, tea. A seemingly simple beverage, a nutritional ghost. It’s a global phenomenon, isn't it? From the ancient misty mountains of Yunnan, China, where Camellia sinensis first unfurled its delicate leaves, to the bustling tea houses of Marrakech, or the serene Japanese tea ceremonies. Billions consume it daily. A ritual, a comfort, a simple pleasure. But try to track it. Go on, I dare you. It’s a Sisyphean task.
Manual tracking for tea is an absolute nightmare. Forget the myth of "plain tea" being a single entity. It’s a culinary chameleon! Black tea, green tea, oolong, white, pu-erh. Each has its own distinct chemical fingerprint, its particular polyphenolic profile. Then you factor in preparation. Steeping time? Water temperature? Infusion strength changes everything. A light brew is barely flavored water. A long, dark steep? That’s a whole different kettle of fish, literally. More solids extracted, more caffeine, more everything.
Then come the additions. This is where the nutritional story utterly derails. A splash of milk. Not just any milk, mind you. Whole, skim, almond, oat, soy—each with its own caloric baggage. A teaspoon of sugar? Easy 20 calories. A dollop of honey? Double that. Lemon slices, ginger, cardamom, cinnamon... all these seemingly innocuous embellishments, they add up. Dramatically. They fundamentally transform that calorie-negligible brew into something entirely different.
Who measures their tea? Really? Nobody I know meticulously weighs out milk or counts sugar granules when making their morning cuppa. A "cup" can be a dainty porcelain teacup, or it can be my monstrous 20oz office mug. The volume variability alone is infuriating. The average user just logs "1 cup black tea." It's woefully inaccurate. A whisper of calories morphs into a significant contributor to daily intake when you add the usual suspects. This isn't just about weight loss; it's about understanding one's true dietary landscape. This blind spot? It's huge.
We need precision. We need to see through the opaque steam and ambiguous mug sizes. This is precisely why NutriSnap is revolutionary. Our AI doesn’t just see "tea." It performs forensic visual analysis. It identifies the type, estimates the steeping intensity from color, detects milk's opacity, even quantifies sugar granules or the viscous sheen of honey. Finally, we can turn the art of tea into the science of nutrition. It’s not just tracking; it’s understanding.
Explore More Research
Tired of Manual Tracking?
Stop scanning barcodes and guessing portion sizes. NutriSnap uses forensic AI to track your macros instantly from a single photo.