Food · Fruit · 热带
Watermelon
92% 是水 · 番茄红素含量不低于熟番茄 (且不需要烹饪) · 独特的瓜氨酸→精氨酸→NO 通路 · GI 高但 GL 极低 —— 西瓜升糖误区拆穿 · 红瓤=番茄红素, 黄瓤没有
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Story path
- 1What is watermelon · 92% waterWhat is watermelon · 92% water
- 2Rich in · lycopene + citrullineRich in · lycopene + citrulline
- 3Key knowledge · high GI but low GL — watermelon does not spike blood sugarKey knowledge · high GI but low GL — watermelon does not spike blood sugar
- 4What it lacks · pairings · seeds and rindWhat it lacks · pairings · seeds and rind
- 5How to choose · cut · storeHow to choose · cut · store
Chapter 1
What is watermelon · 92% water
What is watermelon · 92% water
Watermelon (Citrullus lanatus) is a one-year-growth plant in the cucumber family, native to Africa and now one of the most widely grown fruits in the world. Its most defining feature is almost written in the name: approximately 92% of its content is water.
The consequence of this high water content is that despite tasting very sweet, watermelon contains only about 30 kcal per 100 g. A 300 g slice is roughly 90 kcal with about 21 g of sugar — a satisfying gap between 'feels like I ate a lot' and 'actual calorie intake was modest'.
Red-fleshed vs yellow-fleshed watermelon: the red color comes from lycopene — the same pigment as in tomatoes. Yellow-fleshed watermelon has essentially no lycopene but otherwise similar nutrients. If you value lycopene, choose red-fleshed.
The consequence of this high water content is that despite tasting very sweet, watermelon contains only about 30 kcal per 100 g. A 300 g slice is roughly 90 kcal with about 21 g of sugar — a satisfying gap between 'feels like I ate a lot' and 'actual calorie intake was modest'.
Red-fleshed vs yellow-fleshed watermelon: the red color comes from lycopene — the same pigment as in tomatoes. Yellow-fleshed watermelon has essentially no lycopene but otherwise similar nutrients. If you value lycopene, choose red-fleshed.
Chapter 2
Rich in · lycopene + citrulline
Rich in · lycopene + citrulline
Watermelon has two nutritional components especially worth explaining:
The first is lycopene: raw watermelon contains roughly 4-6 mg lycopene per 100 g. This is comparable to or higher than raw tomato (about 2.6-3.4 mg per 100 g), and watermelon lycopene does not require heating to improve absorption the way tomato's does — eating it raw works well. Lycopene is a fat-soluble carotenoid and absorbs better with a small amount of fat.
The second is L-citrulline: watermelon is the richest dietary source of citrulline, with about 250 mg per 100 g in the flesh and more in the rind. Citrulline is converted in the body to L-arginine, which is then converted to nitric oxide (nitric oxide: A small signal molecule from the vessel lining that relaxes the vessel-wall muscle so the vessel widens.). NO is a vasodilatory signaling molecule involved in blood pressure regulation. Collins et al. (2007) showed that regular watermelon consumption significantly raised plasma arginine levels. However, human evidence for watermelon lowering blood pressure remains preliminary — grade C evidence: an interesting mechanism, not an established clinical conclusion.
Other nutrition: vitamin C about 8-10 mg per 100 g (moderate), provitamin A (from lycopene and beta-carotene), vitamin B6, some potassium. Fiber is low (about 0.4 g per 100 g), calcium and iron are minimal.
The first is lycopene: raw watermelon contains roughly 4-6 mg lycopene per 100 g. This is comparable to or higher than raw tomato (about 2.6-3.4 mg per 100 g), and watermelon lycopene does not require heating to improve absorption the way tomato's does — eating it raw works well. Lycopene is a fat-soluble carotenoid and absorbs better with a small amount of fat.
The second is L-citrulline: watermelon is the richest dietary source of citrulline, with about 250 mg per 100 g in the flesh and more in the rind. Citrulline is converted in the body to L-arginine, which is then converted to nitric oxide (nitric oxide: A small signal molecule from the vessel lining that relaxes the vessel-wall muscle so the vessel widens.). NO is a vasodilatory signaling molecule involved in blood pressure regulation. Collins et al. (2007) showed that regular watermelon consumption significantly raised plasma arginine levels. However, human evidence for watermelon lowering blood pressure remains preliminary — grade C evidence: an interesting mechanism, not an established clinical conclusion.
Other nutrition: vitamin C about 8-10 mg per 100 g (moderate), provitamin A (from lycopene and beta-carotene), vitamin B6, some potassium. Fiber is low (about 0.4 g per 100 g), calcium and iron are minimal.
数字 · 这两个成分到底有多少
上一屏说这两个成分特别, 这一页把量摆出来.番茄红素: 生西瓜约含 4-6 mg/100 g. 这个数字和生番茄相当甚至更高 (生番茄约 2.6-3.4 mg/100 g), 而且西瓜的番茄红素不需要像番茄那样加热才能提高吸收率 —— 直接吃就很好. 番茄红素是脂溶性类胡萝卜素, 配一点脂肪吸收更好.
为什么脂溶这件事值得单独记一笔
很多人对营养流失的印象是维生素 C 那一套: 怕热、怕久泡、切开放久了就没了. 那是水溶性营养素的失分方式. 番茄红素的短板完全不在这条线上 —— 它耐得住加热 (加热反而帮忙把它从细胞里放出来), 它怕的是这一餐里一点油都没有.
道理在于它必须溶进油里才走得动: 脂肪在小肠里被打散成小油滴, 亲油的番茄红素溶进去搭车, 才有机会被肠壁接收. 一餐里完全没有脂肪, 色素就算已经从果肉细胞里出来了, 也只是随着食糜一路过去. 所以西瓜配菲达奶酪、配几粒坚果, 不是讲究, 是这条路上真的少不了的一环.
瓜氨酸: 西瓜是膳食中最丰富的瓜氨酸来源, 果肉约含 250 mg/100 g, 瓜皮更高. 请注意这是每一百克果肉的量, 而人一次吃西瓜很少只吃一小口 —— 份量本身就是西瓜在这条通路上比别的水果特殊的原因.
其他营养: 维生素 C 约 8-10 mg/100 g (中等), 维生素 A 前体 (来自番茄红素和 β-胡萝卜素), 维生素 B6, 少量钾. 纤维很少 (约 0.4 g/100 g), 钙铁微量.
机制 · 为什么是瓜氨酸, 而不是直接补精氨酸
这条链上有一个反直觉的地方: 如果目标是把血里的精氨酸抬上去, 直接吃精氨酸, 效果反而不如吃瓜氨酸.原因在肝脏. 从肠道吸收进来的东西不会直接进入全身血液, 它们先汇进门静脉、整批送到肝脏 —— 肝脏是入关口岸, 有权在放行之前先处理一遍. 而肝细胞里有一把专门拆精氨酸的酶 (精氨酸酶, arginase), 效率很高: 口服的精氨酸大部分在这一关就被拆掉, 真正抵达全身循环的增量很有限.
瓜氨酸走的是另一条路. 它不是那把酶的底物, 过肝脏时基本没人动它, 于是一路进入全身循环; 之后在肾脏被两步酶接手, 转回精氨酸再放出来. 等于绕开了口岸 —— 血里的精氨酸反而抬得更高、也更持久.
所以西瓜的意义不在于它含精氨酸, 而在于它含的是精氨酸的上游前体.
这一条值得从西瓜身上拎出来记住: 吃进去多少和身体拿到多少之间, 隔着一整条代谢路线. 同一个终点, 换一个入口, 到达率可以差很多. 你在补剂货架上看到的很多前体类原料, 讲的都是这同一个道理.
机制 · 一氧化氮钻进血管壁之后, 到底发生了什么
上一屏那句nitric oxide: A small signal molecule from the vessel lining that relaxes the vessel-wall muscle so the vessel widens. 让平滑肌松开, 是这条链上最容易被一句话带过、也最值得看清的一环. 放大来看.先分清血管壁的两层
内皮: 血管最里面那一层细胞, 直接泡在血流里. 精氨酸就是在这里被做成 NO 的平滑肌: 内皮外面一圈环形排列的肌肉. 它绷紧, 管腔就收窄; 它松开, 管腔就变宽
NO 是气体, 所以它不需要敲门
大多数信号分子得在细胞表面找到自己的受体才能传话. NO 不用: 它是个极小的气体分子, 在内皮细胞里生成之后直接扩散穿过细胞膜, 进到紧挨着的平滑肌细胞里.
代价是它跑不远、也活不久 —— 它只对隔壁说话. 这一点解释了一件很实际的事: 血流调节因此可以做到一段血管一段血管地单独调, 哪里在干活哪里就放宽, 而不是全身血管一起开关.
进了平滑肌之后
NO 在平滑肌细胞里找到一把专门等着它的信号酶并打开它; 这把酶开始生产一个第二信使 (cGMP); cGMP 再让细胞内的钙降下来. 肌肉收缩靠的就是钙 —— 钙一降, 那一圈环形肌整体松开, 管腔跟着变宽.
管腔变宽的下游后果
同一颗心脏推同样多的血, 如果下游的管子整体更松, 遇到的阻力就更小. 这一段对应的正是外周阻力 —— 血压里舒张压那一半, 尤其依赖它.
讲到这里必须踩一脚刹车: 以上全部是机制上说得通, 离吃西瓜能降血压还差好几步. 下一页专门讲这段距离有多远.
证据 · 这条链走到哪一步就停了
机制讲得越顺, 越要说清它在哪儿停下.Collins 等 (2007) 的研究显示, 连续摄入西瓜后血浆精氨酸水平显著升高. 这是一个中间指标: 它证明了链条的前半截在人身上确实走得通 —— 吃西瓜, 血里的精氨酸真的上去了.
但血压有没有跟着下来是另一个问题, 那需要的是终点指标. 目前关于西瓜降血压的人体证据仍是初步的, 属于 C 级证据 —— 有意思的机制, 不是确立的临床结论.
为什么中间指标和终点指标必须分开看
一条通路上的任何一环都可能被别的因素补偿掉:
精氨酸升高了, 内皮不一定按比例多做出 nitric oxide: A small signal molecule from the vessel lining that relaxes the vessel-wall muscle so the vessel widens.NO 多了, 平滑肌不一定按比例多松开血管松了, 肾脏和神经系统仍在同时调节血压, 可能把这点变化抵消回去
每多一个环节, 从指标动了推到人受益了就多一分不确定. 这也是为什么同一条机制在杯子里、在老鼠身上、在人的血样里、在人的血压计上, 说服力完全不是一个量级.
这个区分不只用在西瓜上
补剂广告和健康新闻里的已被研究证实, 绝大多数停的都是中间指标那一站. 下次看到这类说法, 只要多问一句 —— 这个研究测的是指标, 还是结局? —— 你的判断力就已经超过大部分转发它的人了.
Chapter 3
Key knowledge · high GI but low GL — watermelon does not spike blood sugar
Key knowledge · high GI but low GL — watermelon does not spike blood sugar
Watermelon is the classic nutrition textbook example of the GI versus GL distinction:
Watermelon's glycemic index (GI) is approximately 72-76 — classified as a high-GI food. This causes many people, especially those with diabetes, to avoid it.
But the glycemic index measures 'how fast the carbohydrates in this food type raise blood sugar,' not 'how high your blood sugar will actually rise from eating this serving.' To estimate the latter, you need glycemic load (GL):
GL = GI × grams of digestible carbohydrate per serving / 100
Watermelon is 92% water. A 120 g serving contains only about 8.5 g digestible carbohydrate:
GL = 76 × 8.5 / 100 ≈ 6.5 — this is a low glycemic load (GL < 10 = low).
For comparison: a bowl of white rice (200 g cooked) contains about 46 g carbohydrate, GL of about 40+.
Reasonable conclusion: a normal portion of watermelon (one or two pieces, about 200-300 g) has a very small actual blood-sugar impact and should not be blanket-avoided based on the GI number. For people with diabetes, portion control plus self-monitoring plus medical guidance is the appropriate approach.
'Watermelon spikes blood sugar' is technically half-right (GI is high) but practically misleading (GL is low).
Watermelon's glycemic index (GI) is approximately 72-76 — classified as a high-GI food. This causes many people, especially those with diabetes, to avoid it.
But the glycemic index measures 'how fast the carbohydrates in this food type raise blood sugar,' not 'how high your blood sugar will actually rise from eating this serving.' To estimate the latter, you need glycemic load (GL):
GL = GI × grams of digestible carbohydrate per serving / 100
Watermelon is 92% water. A 120 g serving contains only about 8.5 g digestible carbohydrate:
GL = 76 × 8.5 / 100 ≈ 6.5 — this is a low glycemic load (GL < 10 = low).
For comparison: a bowl of white rice (200 g cooked) contains about 46 g carbohydrate, GL of about 40+.
Reasonable conclusion: a normal portion of watermelon (one or two pieces, about 200-300 g) has a very small actual blood-sugar impact and should not be blanket-avoided based on the GI number. For people with diabetes, portion control plus self-monitoring plus medical guidance is the appropriate approach.
'Watermelon spikes blood sugar' is technically half-right (GI is high) but practically misleading (GL is low).
数字 · 把这笔账算给你看
西瓜的血糖指数 (GI) 大约是 72-76 —— 属于高 GI 食物. 这让很多人, 尤其是糖尿病患者, 对西瓜望而却步.血糖负荷的算法只有一行:
GL = GI × 每份食物中可消化碳水化合物 (g) / 100
西瓜 92% 是水, 一份 120 g 的西瓜只含约 8.5 g 可消化碳水:
GL = 76 × 8.5 / 100 ≈ 6.5 —— 这是低血糖负荷 (GL < 10 = 低).
对比: 一碗白米饭 (200 g 熟) 含约 46 g 碳水, GL 约 40 以上.
注意这个对比里两个数各自的角色: 白米饭和西瓜的 GI 是同一档的高, 拉开差距的完全是这一份里有多少碳水那一项. 同样的公式, 同样的高 GI, 结果差了将近一个数量级.
合理结论: 正常份量的西瓜 (一两块, 约 200-300 g), 对血糖的实际冲击很小, 不应该因为 GI 数字而一刀切地避开. 对糖尿病患者, 控制份量 + 血糖自我监测 + 配合医嘱才是正确方式.
西瓜升糖这个说法技术上有一半是对的 (GI 高) 但实践上往往是误导的 (GL 低).
机制 · 一样东西怎么会又快又少
GI 高、GL 低听起来像自相矛盾. 把它放回身体里走一遍就通了.为什么快 (GI 高)
一块西瓜进了胃, 里面绝大部分是液体. 胃排空液体本来就比排空固体快得多, 于是这口食物很快被送进小肠 —— 而糖被吸收进血液的地方正是小肠. 到得早, 血糖曲线爬升就陡.
再加上西瓜纤维极少、几乎没有脂肪和蛋白质:
纤维会让肠道里的食糜变黏, 拖慢糖分子接触肠壁的速度脂肪和蛋白质会让胃更慢地往下放行
这几样西瓜一样都没有, 等于全程没有减速带.
为什么少 (GL 低)
但同一块西瓜里, 糖的总量很小 —— 它的重量绝大部分是水. 快, 说的是那些糖分子到达血液的速度; 少, 说的是一共到了多少个. 血糖被推多高, 取决于同一时刻血里多出来多少葡萄糖分子, 那是速度和数量一起决定的, 而西瓜在数量这一项上很小.
换个说法
GI 像在问水龙头开得多大, GL 才是在问这一桶水一共有多少. 龙头开到最大, 桶里只有一杯水, 地上也淹不了.
这个工具怎么用在别的食物上
同样是高 GI, 一份西瓜和一片白面包完全不是一回事 —— 差别在同样重量里碳水的密度干货 (米、面、饼干、果干) 天生碳水密度高, 高 GI 会直接翻译成高 GL水多的整果 (西瓜、草莓、甜瓜) 即使 GI 不低, 一份的 GL 通常也低榨成汁就变了: 纤维被滤掉、体积被压小, 同样多的糖挤进更小的一口 —— 这是少数几个你在自家厨房里就能把 GL 推上去的动作
最后一句实话: GI 和 GL 都是平均意义上的数. 同一份西瓜, 冰的和常温的、空腹吃和饭后吃、一个人和另一个人, 血糖曲线都不一样. 它们是帮你排除因为一个数字就一刀切的工具, 不是精确预测器.
Chapter 4
What it lacks · pairings · seeds and rind
What it lacks · pairings · seeds and rind
Watermelon's clear shortcomings: almost no protein (about 0.6 g per 100 g), almost no fat, very low fiber (0.4 g per 100 g), minimal calcium and iron, no B12 or vitamin D. Watermelon's strengths are hydration, vitamin C, and lycopene in the summer heat; it cannot carry a full meal on its own.
Pairing ideas:
With fat-containing foods (cheese, nuts): helps lycopene absorption; watermelon with feta cheese is a traditional Mediterranean pairing that is nutritionally logicalWith protein (yogurt, legumes): adds the protein watermelon almost entirely lacksJuice vs whole: juicing removes the small amount of fiber and concentrates sugar in liquid form for faster absorption. Eating whole slices is better than drinking juice
On watermelon seeds: black seeds contain meaningful amounts of zinc, magnesium, and plant protein; roasted as a snack they are worthwhile. Seedless watermelons are conventional hybrids (triploid breeding), not genetically modified.
On watermelon rind: the white rind flesh is even higher in citrulline than the red flesh, and is eaten stir-fried in some culinary traditions (Chinese-style stir-fried watermelon rind). Nutritionally the white rind has value, just in a different culinary form.
In one line: watermelon's greatest value is low-calorie, lycopene-containing hydration in hot weather — a summer staple, not a complete nutritional food.
Pairing ideas:
With fat-containing foods (cheese, nuts): helps lycopene absorption; watermelon with feta cheese is a traditional Mediterranean pairing that is nutritionally logicalWith protein (yogurt, legumes): adds the protein watermelon almost entirely lacksJuice vs whole: juicing removes the small amount of fiber and concentrates sugar in liquid form for faster absorption. Eating whole slices is better than drinking juice
On watermelon seeds: black seeds contain meaningful amounts of zinc, magnesium, and plant protein; roasted as a snack they are worthwhile. Seedless watermelons are conventional hybrids (triploid breeding), not genetically modified.
On watermelon rind: the white rind flesh is even higher in citrulline than the red flesh, and is eaten stir-fried in some culinary traditions (Chinese-style stir-fried watermelon rind). Nutritionally the white rind has value, just in a different culinary form.
In one line: watermelon's greatest value is low-calorie, lycopene-containing hydration in hot weather — a summer staple, not a complete nutritional food.
数字 · 短板到底有多短
上一屏用了几乎没有这个说法. 具体是这个量级: 蛋白质约 0.6 g/100 g, 纤维 0.4 g/100 g.这两个数小到一件事: 即使你一次吃掉一大块西瓜, 它对你一天的蛋白账本和纤维账本仍然近似于零. 所以西瓜的位置是加在饮食里的水果, 不是替掉一顿饭的东西 —— 用它顶一餐, 你顶掉的是蛋白质和纤维, 而这两样恰恰是最难在别处补回来的.
机制 · 几乎全是水, 为什么反而是它的功能
把几乎全是水当成西瓜的缺点, 是看错了它的位置. 在夏天, 那正是它做的事.出汗流掉的不只是水
汗里还带走钾、钠这类电解质. 只灌白水, 补回来的是水那一半; 而西瓜送进来的是带着钾和糖的水.
糖在这里也不全是负担. 小肠上皮细胞在吸收葡萄糖的时候, 会顺带把钠一起拖进细胞; 钠一进去, 水就跟着离子的方向被拉过去. 这也是口服补液盐要同时含糖和盐的原因 —— 糖不是为了甜, 它是钠的搬运搭档, 而水跟着钠走.
但要说清分寸
西瓜不是运动饮料, 它的钾只是少量这个级别, 别把它当电解质补充剂用. 它真正管用的地方是另一件事: 天热的时候很多人根本不想喝水, 而一块西瓜能让你不知不觉喝下去一大杯水的量. 补水最大的瓶颈从来不是喝了多少能吸收, 而是你到底肯不肯喝.
关于榨汁, 再补一句机制
榨汁这一步同时做了三件事: 滤掉本来就不多的纤维、把体积压小、让糖更快到达小肠. 前两件让同样一杯里的糖变多, 第三件让它到得更快 —— 正好是上一幕里推高血糖负荷的那两个方向一起动. 整块吃还得靠牙齿和时间, 那本身就是一道减速带.
Chapter 5
How to choose · cut · store
How to choose · cut · store
Choosing a whole watermelon: heft it (heavier means more water); knock it (a hollow, low-pitched sound is usually a sign of ripeness); look at the field spot on the underside — creamy yellow means it ripened long enough on the ground; white or green means it was picked too early.
Choosing a cut watermelon: look for deep, uniform red flesh and avoid pieces with lots of white 'stringiness' — that is fiber bunching, which affects texture. Large, plump seeds usually indicate ripeness.
Storage:
Whole, uncut: room temperature for a few days to two weeks (depends on ripeness at purchase)Cut: immediately cover the cut surface with plastic wrap, refrigerate, eat within 3-5 days. Chilled watermelon also has better flavorFreezing: cut into chunks and freeze for smoothies; texture becomes softer and watery after thawing
'Watermelon must not be combined with other foods': no nutritional basis. Watermelon plus yogurt, watermelon plus mint, watermelon with a squeeze of lemon — all fine.
How much: one or two pieces (200-300 g) as a fruit dessert is a reasonable portion. Very large amounts (over 1 kg at a time) accumulate significant sugar. On hot summer days when drinking enough water is challenging, watermelon is an effective hydrating food.
Choosing a cut watermelon: look for deep, uniform red flesh and avoid pieces with lots of white 'stringiness' — that is fiber bunching, which affects texture. Large, plump seeds usually indicate ripeness.
Storage:
Whole, uncut: room temperature for a few days to two weeks (depends on ripeness at purchase)Cut: immediately cover the cut surface with plastic wrap, refrigerate, eat within 3-5 days. Chilled watermelon also has better flavorFreezing: cut into chunks and freeze for smoothies; texture becomes softer and watery after thawing
'Watermelon must not be combined with other foods': no nutritional basis. Watermelon plus yogurt, watermelon plus mint, watermelon with a squeeze of lemon — all fine.
How much: one or two pieces (200-300 g) as a fruit dessert is a reasonable portion. Very large amounts (over 1 kg at a time) accumulate significant sugar. On hot summer days when drinking enough water is challenging, watermelon is an effective hydrating food.
误区 · 西瓜不能和 X 一起吃, 在身体里找不到落点
西瓜不能配虾, 西瓜配桃子会中毒 —— 这类说法每年夏天都会转一轮. 与其一条条去背哪些能配哪些不能配, 不如看清它们共同的漏洞在哪.你吃下去的东西不会分开排队
食物在胃里的第一件事是被搅成糊. 胃壁的肌肉一层横一层斜地收缩, 把这一餐所有内容和胃液混在一起, 变成一团均匀的食糜, 再一小份一小份地放进小肠. 也就是说, 到消化真正开始的时候, 哪一口是西瓜、哪一口是虾, 身体已经分不出来了.
再往下, 消化是按分子类别分工的: 拆蛋白的酶只管蛋白, 拆淀粉的酶只管淀粉, 脂肪要等胆汁乳化. 没有哪一把酶的工作方式是遇到西瓜就改变对虾的处理.
所以真正该问的是三个具体问题
量: 一次吃了多少? 一口气吃掉一大盆冰西瓜, 肚子不舒服是冷 + 量大 + 糖多的结果, 和搭配无关本人: 你本来就对其中某样过敏或不耐受吗? 那是这一样东西的问题, 不是相克卫生: 切开放了很久的西瓜, 表面是细菌很好的培养基. 夏天吃坏肚子, 这一条的概率远高于任何搭配
记住这个提问方式比记住结论有用
下次再看到A 不能和 B 同吃, 不必去查真假, 先问一句: 它说的是身体里的哪一步出了问题? 说不出那一步, 就只是一句听起来很像知识的话.
References · 5
- U.S. Department of Agriculture, Agricultural Research Service. (2019). FoodData Central: Watermelon, raw. ~30 kcal/100 g; ~92% water; lycopene ~4-6 mg/100 g; L-citrulline ~250 mg/100 g flesh; vitamin C ~8-10 mg/100 g; fiber ~0.4 g/100 g; glycemic index ~72-76. fdc.nal.usda.gov
- Collins, J. K., Wu, G., Perkins-Veazie, P., Spears, K., Claypool, P. L., Baker, R. A., & Clevidence, B. A. (2007). Watermelon consumption increases plasma arginine concentrations in adults. Nutrition, 23(3), 261-266. Feeding study in 23 adults: watermelon consumption raised plasma L-arginine and L-citrulline; citrulline (~250 mg/100 g flesh, more in rind) is converted to arginine and subsequently to nitric oxide. Small-scale mechanistic study; blood-pressure endpoints not assessed here. 10.1016/j.nut.2007.01.005
- Perkins-Veazie, P., Collins, J. K., Pair, S. D., & Roberts, W. (2001). Lycopene content differs among red-fleshed watermelon cultivars. Journal of the Science of Food and Agriculture, 81(10), 983-987. Lycopene varied by cultivar (~3.8-7.1 mg/100 g fresh weight), establishing red-fleshed watermelon as a lycopene source comparable to tomato. 10.1002/jsfa.880
- Edwards, A. J., Vinyard, B. T., Wiley, E. R., Brown, E. D., Collins, J. K., Perkins-Veazie, P., et al. (2003). Consumption of watermelon juice increases plasma concentrations of lycopene and beta-carotene in humans. The Journal of Nutrition, 133(4), 1043-1050. A 19-week controlled crossover feeding study: lycopene from non-heat-treated watermelon juice was as bioavailable as lycopene from heat-processed canned tomato juice. 10.1093/jn/133.4.1043
- Foster-Powell, K., Holt, S. H. A., & Brand-Miller, J. C. (2002). International table of glycemic index and glycemic load values: 2002. The American Journal of Clinical Nutrition, 76(1), 5-56. Comprehensive reference table of GI and GL values for 750 foods tested in human subjects; GL = GI × available carbohydrate per serving / 100, providing an integrated measure of blood-glucose impact per realistic portion. 10.1093/ajcn/76.1.5