Most non-starchy vegetables are low in carbs, but some stand out as especially light. Leafy greens like spinach and arugula contain barely 1 gram of carbs per serving, while cruciferous options like broccoli and cauliflower hover around 4 to 6 grams per cup. If you’re counting carbs for keto, diabetes management, or general health, vegetables should be the last thing you cut. Here’s a practical breakdown of the best options and how to use them.
Leafy Greens: The Lowest You Can Go
Leafy greens sit at the very bottom of the carb scale. A cup of raw spinach (30 g) has just 1.1 grams of total carbs with 0.7 grams of fiber, leaving roughly 0.4 grams of net carbs. A half cup of arugula comes in even lower at 0.4 grams total. Swiss chard, at 1.4 grams per raw cup, is another excellent choice. You can eat enormous salads of these greens without making a meaningful dent in your daily carb count.
Kale is slightly higher but still very low when eaten raw. A cup of raw kale (21 g) is negligible, though a cup of cooked kale (118 g) jumps to 6.3 grams of total carbs because cooking concentrates the volume. That same cooked cup also delivers 4.7 grams of fiber, so the net carb count drops to about 1.6 grams. Lettuce rounds out the category at roughly 1 to 2 grams per cup depending on the variety, making it a reliable base for any meal.
Cruciferous Vegetables: Low Carbs, High Versatility
Broccoli, cauliflower, Brussels sprouts, and cabbage are some of the most useful vegetables on a low-carb plan because they can stand in for higher-carb foods. Cauliflower rice, mashed cauliflower, and broccoli-cheddar dishes give you bulk and satisfaction without spiking your carb intake.
A cup of raw broccoli (91 g) has about 6 grams of total carbs, and a cup of raw cauliflower (107 g) is similar at around 5 grams. A cup of chopped raw cabbage (89 g) lands near 5 grams as well. A half cup of cooked Brussels sprouts (78 g) sits in the same range. These vegetables also have very low glycemic index scores: Brussels sprouts score a 6, broccoli a 10, and cauliflower a 12 on a scale where anything under 55 is considered low. That means they cause minimal blood sugar movement even beyond what their carb counts suggest.
Other Vegetables Under 6 Grams Per Serving
Beyond greens and cruciferous options, plenty of other vegetables keep carbs in check:
- Zucchini and summer squash: A half medium squash (98 g) has 4 grams of total carbs with 2 grams of fiber. A full cup of raw zucchini (124 g) is similar. These are a go-to pasta substitute when spiralized.
- Cucumbers: A cup of chopped cucumber (104 g) comes in around 3 to 4 grams, mostly water and fiber.
- Celery: A cup of chopped celery (101 g) has about 3 grams of carbs, making it one of the lowest-carb snacking vegetables.
- Radishes: A cup of raw sliced radishes (116 g) sits around 4 grams and works well as a roasted potato substitute.
- Mushrooms: A cup of raw white mushrooms (70 g) has roughly 2 to 3 grams total.
- Asparagus: A cup of cooked asparagus (180 g) has about 7 grams total but around 4 grams fiber, bringing net carbs to approximately 3 grams.
Bell peppers deserve special mention. One medium bell pepper (148 g) has 6 grams of total carbs with 2 grams of fiber and 4 grams of natural sugars. That’s slightly higher than some options on this list, but a single pepper delivers 190% of your daily vitamin C. Green peppers tend to be a bit lower in sugar than red, yellow, or orange varieties.
Tomatoes, green beans, eggplant, and onions all fall in the moderate-low range of roughly 5 to 8 grams per cup. They’re fine for most low-carb approaches, though if you’re aiming for under 20 grams per day on strict keto, you’ll want to measure portions of these more carefully.
Vegetables That Are Higher Than You’d Expect
Not all vegetables are low-carb. Several common options pack 14 grams or more of total carbs per 100 grams, which can quickly eat into a daily limit. Potatoes have about 16 grams per 100 grams raw, sweet potatoes around 17.3 grams, and yams climb to 27.4 grams when cooked. Corn lands at 14.7 grams, peas at 14.45 grams, and cooked parsnips at 16.5 grams.
These aren’t unhealthy foods by any stretch. They’re packed with vitamins, minerals, and fiber. But if your goal is staying under a specific carb ceiling, a single medium potato can account for a third or more of your daily allowance. The simple rule: above-ground vegetables tend to be lower in carbs, while roots, tubers, and legumes tend to be higher.
Net Carbs vs. Total Carbs
When you see carb counts for vegetables, it helps to know the difference between total and net carbs. Net carbs equal total carbohydrates minus fiber, since your body doesn’t digest fiber the same way it digests sugar or starch. Fiber passes through largely intact and doesn’t raise blood sugar.
This distinction matters most with high-fiber vegetables. Cooked kale drops from 6.3 grams total to just 1.6 grams net. Summer squash goes from 4 grams total to about 2 grams net. If you’re tracking carbs for blood sugar control, net carbs give you a more accurate picture of what’s actually affecting your glucose levels. Most keto plans count net carbs, which is one reason vegetables fit more easily than their total carb numbers might suggest.
Cooking and Storing for Best Results
How you cook low-carb vegetables doesn’t change their carb content, but it can affect the vitamins you get from them. Higher temperatures and longer cooking times cause the most nutrient loss, particularly for water-soluble vitamins like C and several B vitamins. Quick methods like stir-frying, microwaving, and pressure cooking preserve more nutrients than boiling or long baking sessions.
Roasting with a small amount of oil is a good middle ground. The oil speeds cooking time and helps your body absorb fat-soluble vitamins from the vegetables. Adding raw greens directly to soups, stews, or sauces near the end of cooking is another effective approach, since the nutrients stay in the liquid you’re eating rather than getting discarded.
For storage, frozen vegetables retain similar vitamin, mineral, and phytonutrient levels compared to fresh, so keeping bags of frozen broccoli, cauliflower, or spinach on hand is a perfectly sound strategy. When prepping fresh vegetables, wash gently but skip the long soak, and cut them just before cooking rather than hours ahead. Exposure to oxygen and light degrades nutrients over time.