No Appetite, Drowsy All Day, and Completely Wiped Out Every Summer? Doctor Luo Dalun’s Three Rules for Protecting the Spleen and Stomach: Eat Light, Never Crave Cold Drinks, and Resolve Dampness

Opening: as soon as summer arrives, you feel like a wreck

Many of us know the feeling: the moment the weather turns hot, the appetite vanishes first; by noon the eyelids are so heavy they fight each other; the whole body feels lazy, with no strength for anything — you just want to lie down — yet when you actually lie down you can’t sleep, tossing and turning. In winter it’s nothing like this. So why do heat, drowsiness and loss of appetite come together every summer?

💬 Note from Doctor Luo: Let’s set aside Doctor Luo Tianyi’s cases today and talk about something off-topic — but it’s still about the spleen and stomach, the spleen-stomach theory we’ve been discussing all along. Today we combine theory with real life: how do we protect our spleen and stomach in summer? Many friends feel that as soon as the weather heats up, they lose their appetite. What’s going on with the spleen and stomach in summer, and how do we protect them?

Why does heat make you drowsy? — animals are the same, and Singapore runs its air conditioning at 18°C

Let’s set aside Chinese medicine for a moment and start with plain common sense. In summer, human bodies really do change — and it’s not just humans; animals change too.

💬 Note from Doctor Luo: Look at kittens, puppies and monkeys — at noon they’re all drowsy and want to sleep. Why? It’s a product of evolution. When the weather is hot, our whole circulation speeds up — the ancients said the summer pulse tends to be full, fast and floating, precisely because blood is a liquid: it congeals when cold and flows freely when warm, so in summer the body runs in high-efficiency mode.

But high efficiency comes at a price: to survive in the heat, the body must burn a great deal of energy. To save energy, it automatically drops into a relatively low-power state.

💬 Note from Doctor Luo: If you insist on strenuous exercise at this time — going out to play badminton at noon in 40-degree heat — you’re just adding torture to the body. So over the course of evolution the body developed this mechanism: when the weather is extremely hot and the qi and blood are already moving fast, we reduce activity and enter a state somewhat like sleep, cutting energy consumption. All animals do this — cats are drowsy at noon, monkeys take midday naps — it’s a natural result of evolution.

Here’s another detail: total blood volume is fixed. When it’s hot, the pores open and blood is sent out to the four limbs and every part of the body, and circulation speeds up — in effect, nearly all the blood reserves are mobilized, so the amount reaching each individual part decreases. The head gets slightly less blood, so you feel drowsy; the spleen-stomach digestive system gets less blood, so your appetite naturally drops. This is simply the body’s qi and blood being redistributed.

💬 Note from Doctor Luo: So a somewhat reduced appetite in summer — not wanting to eat too much — is normal, and you shouldn’t worry about it. Here’s an example: why is indoor air conditioning in Singapore permanently set to 18 degrees? That was set by Prime Minister Lee Kuan Yew back then — he said people in tropical regions tend to be sluggish and work less efficiently, so never mind the electricity bill, crank the air conditioning, get people alert, and work efficiency goes up. People really do get lazy when it’s hot — there’s a reason for it.

Protective principle one: eat lighter in summer

Now that we understand the mechanism, let’s talk about how to protect yourself. Rule one: don’t eat high-calorie food in summer.

💬 Note from Doctor Luo: If you say, “In summer I braise pork ribs and red-cooked pork” — no, absolutely not. Why? A large amount of heat comes in with nowhere to go. The whole body is already in a hot state, and it wants to calm down — outside is hot, inside is hot, and the energy cost is unbearable. So in summer your food should be lighter and your portions a little smaller. This follows the laws of nature.

Each region’s food matches its climate: in the cold northeast, people love rich meat and fish in winter, using calories to fight the cold outside; on Hainan Island, people are satisfied with a bowl of noodles — a small meal is enough. When it’s that hot, if you pour in more calories, they can’t be transformed and the body can’t cope. So in summer, cold noodles, congee, mung-bean congee and lotus-leaf congee are all good choices.

Protective principle two: never crave cold — it feels good, but the consequences are lasting

The second rule deserves special attention: don’t eat too many cold things in summer.

💬 Note from Doctor Luo: Many people think, “It’s so hot — an iced drink, or cold noodles with ice cubes, feels so comfortable.” But what feels comfortable isn’t necessarily good for the body — eating cold things in summer brings lasting consequences. In ancient times ordinary people couldn’t get cold treats; who could? The emperor. There’s a Song-dynasty medical case of an emperor who ate ice and cold drinks, then suffered terrible vomiting and diarrhea, and the imperial physicians had to treat his diarrhea.

Why does a cold drink injure so severely? The key lies in the body’s summer state:

💬 Note from Doctor Luo: In summer we say “yang qi is on the outside” — outside it seems very hot, but inside the body maintains a relatively cool temperature, yin qi is within. The body pays energy to hold this constant-temperature state — like a refrigerator: to keep the inside cold, it has to consume electricity, which is why the outside of the fridge feels warm. People in summer are the same: outside it’s 40 degrees, and the body’s control trend is to bring the temperature down. Now if you add cold things on top of that, you get hurt very easily. Think of it this way: you’re walking down a slope, your momentum is already downward — then an extra force pushes you from above and you tumble and roll all the way down. Chinese medicine looks at a feeling, a tendency: in summer it’s very hard to make the body hot, but very easy to make it cold — and making the body cold is exactly what we’re most prone to do.

Doctor Luo has seen far too many real examples:

💬 Note from Doctor Luo: Someone took a big watermelon out of the fridge, ate half of it before bed, and the next day had a fever and violent vomiting and diarrhea and ended up in hospital — yang qi is easily injured, and when cold qi builds up seriously inside, that’s what happens. Someone soaked their legs in ice water to cool off in summer, and got a chronic illness that couldn’t be cured for years — a bellyache, always cold diarrhea. Someone else slept belly-up on a bamboo mat in summer, with the window open all night; the night air was cold as water, and the next day came vomiting, diarrhea and high fever — utterly miserable. So there are very many people whose spleen and stomach get chilled in summer — room temperature, or warm, is the baseline. Never eat iced things; ice injures the spleen and stomach badly.

Protective principle three: beware dampness trapping the spleen

Rule three: in summer, your diet can easily make the body damp.

💬 Note from Doctor Luo: In summer the external dampness is already heavy — when it’s hot, water vapor evaporates, giving us sauna days; and in late summer (the period before autumn) the outside dampness grows even heavier. The internal environment is the same: heat makes you sweat, fluids evaporate with the sweat, and the body sends a strong thirst signal — and once thirsty, people tend to drink a lot. I often see people whose bellies are swollen like a ball from drinking at night, and they still feel thirsty. Iced water makes you thirstier the more you drink; sugary sweet drinks never quench thirst. The body can’t transform these fluids into jin ye (body fluids), so they become dampness pathogen (shi xie) blocked inside — which is why dampness builds up in summer.

When dampness builds up, the first thing it traps is the spleen. In Five-Element theory, the spleen belongs to earth, and earth controls water — water comes, earth holds it back. But if the water gets too big, it can actually flood the earth — as the classics put it, “the spleen earth is submerged in a pond of water.”

💬 Note from Doctor Luo: Dampness trapping the spleen ends up injuring the spleen and stomach. In summer the appetite is already low; add heavy dampness and you lose your appetite entirely — you may even feel achy, bloated and miserable. At that point you need to drain dampness and strengthen the spleen. There’s a proper way to drink water too: warm water, or tea, quenches better and is easier for the body to use, because it hasn’t injured yang qi. Iced water and sweet drinks especially increase dampness. And eating too many cold-natured fruits (like watermelon), especially when they’re ice-cold, also affects the spleen earth.

Dampness trapping the spleen isn’t just uncomfortable — it lets pathogens slip in while you’re weak:

💬 Note from Doctor Luo: Let me give an example — cholera. When Vibrio cholerae enters a healthy person’s spleen and stomach, stomach acid kills it quickly. But sometimes it can’t: on a hot summer day the water is contaminated with the bacterium, you gulp down a lot of water, which dilutes the stomach acid; you’re drinking cold water, which lowers gastrointestinal function; and the spleen-stomach function is already weak in summer anyway. The result: insufficient stomach acid and declining spleen-stomach function — the cholera bacterium comes in, meets no defense, and multiplies fast. That’s why cholera is so prone to epidemic in tropical regions. Many intestinal infectious diseases work the same way. So in summer we need to guard against the collapse of the spleen-stomach system — people with weak spleens and stomachs especially need regulating.

Summer regulation step one: tonify the spleen and qi

So how do you actually regulate? Step one: tonify the spleen — the spleen-stomach weakness shows up more clearly in summer.

💬 Note from Doctor Luo: People who work hard physically every day, who are strong and vigorous, can still eat meat at mealtime — they can transform it, and their labor burns it off. But many office workers have weak spleens and stomachs: in summer they already have little appetite, they’ve drunk too many cold drinks, dampness is heavy, and the icy drinks have injured spleen yang — so they need regulating. How? Use whole grains — for example, Huai yam (huai shan yao) and lotus seeds (lian zi rou) — add a little to your congee while cooking and it tonifies the spleen. Drink these spleen-tonifying foods steadily, and when spleen qi is sufficient, the body’s ability to control its internal environment and coordinate with the outside world grows stronger.

Tonifying the spleen is really tonifying qi — when the spleen and stomach are strong enough to absorb nourishment, the qi of the whole body can genuinely become sufficient.

💬 Note from Doctor Luo: Extremely hot summer weather consumes qi — the body has to maintain balance with the outside world, and the hotter it is outside, the more upright qi you must spend to hold a relatively constant state inside. That’s why qi-deficient people feel unwell the moment they enter a very hot environment — dizziness, racing heartbeat. So in summer, qi-deficient people must pay attention to tonifying qi appropriately. You can use a little American ginseng (xi yang shen), plus some spleen-tonifying foods — tonify the spleen and nurture the qi together.

Summer regulation step two: resolve dampness — lotus leaf, coix seed, and bai dou kou

Step two: drain dampness. What does a damp-heavy person look like? A very thick tongue coating, a tired heavy body, no strength at all, extreme fatigue.

💬 Note from Doctor Luo: A thick tongue coating says the dampness is heavy. In summer you can use things that resolve dampness — we’ve covered a lot of this in the Luo Tianyi cases; the Li Dongyuan school was especially good with lotus leaf. When Zhang Yuansu created Zhi Zhu Wan (Immature Bitter Orange and Atractylodes Pill), he used zhi shi and bai zhu, and after the herbs were prepared he wrapped rice in lotus leaf and steamed it; then he mashed the steamed rice into a paste and made the pill with it.

Here’s a delightful story:

💬 Note from Doctor Luo: Li Dongyuan kept puzzling: why did his master Zhang Yuansu insist on steaming the rice wrapped in lotus leaf? He thought about it for years. Only at the end of his life did he finally understand — lotus leaf raises the clear and lowers the turbid (sheng qing jiang zhuo), and it dispels summer dampness. Using it as the guiding ingredient actually boosts the formula’s power to raise the clear and lower the turbid and to clear summer dampness. So take a few lotus leaves from the pharmacy, cut them into fine shreds, and cook a small pinch together with rice — lotus-leaf congee has the effect of clearing summer dampness. Coix seed (yi ren) and red adzuki beans (chi xiao dou) cooked into congee in summer also drain dampness.

There are fine points in cooking too:

💬 Note from Doctor Luo: When cooking, add a little bai dou kou (white cardamom) or cao dou kou (greater cardamom) — these herbs rouse the spleen-stomach qi, and they also resolve dampness. These are what the Li Dongyuan and Luo Tianyi school called “wind herbs” (feng yao) — herbs that dispel wind can dispel dampness; in essence they rouse the yang qi of the body and move qi and free the channels. All of these herbs are fragrant, and the spices you add in cooking — bai dou kou, cao dou kou — all resolve dampness, so use more of them in summer.

Summer regulation step three: nourish yin — sour-sweet yin transformation, and sour plum soup that really quenches

Step three: protect yin. Yin-deficient people also suffer terribly in summer — especially those whose spleen yin and stomach yin are insufficient.

💬 Note from Doctor Luo: What does spleen-yin deficiency or stomach-yin deficiency feel like? Constant dry heat, a stomach that feels as if it’s on fire, no appetite, and everything you look at seems hot — note, this is different from the classic “yin deficiency with a ravenous appetite.” Yin-deficient people in summer actually have NO appetite; eating something cold seems to make them a little more comfortable. But feeling comfortable from cold food does no good for the body. What to do? Nourish yin, replenish jin ye (body fluids).

Why is it that yin-deficient people never quench their thirst in summer no matter how much water they drink?

💬 Note from Doctor Luo: In summer people drink a lot of water, but because their upright qi (zheng qi) is insufficient, the body may not be able to transform the water into body fluids. Many yin-deficient people drink until their bellies are big and round, and they’re still thirsty, still burning — the body simply can’t turn that liquid into the yin substance it needs inside. This is what Chinese medicine calls “suan gan hua yin” — sour and sweet together, transforming into yin: when sour flavors and sweet flavors are combined, the body finds it easier to convert liquid into absorbable yin substance. So you can drink sour plum soup (suan mei tang) — I’ve given the recipe many times: wu mei (smoked plum) with a little chen pi (aged tangerine peel), a little shan zha (hawthorn berry), a little rock sugar, and osmanthus if you like, boiled into water. Drink this sour plum soup and it genuinely quenches your thirst — your belly won’t be big and round while you’re still thirsty, because the liquid has been transformed into yin substance.

When should you reach for the sour plum soup? Doctor Luo gives clear signals:

💬 Note from Doctor Luo: In summer, if you notice your urine volume dropping, your urine turning yellow, heavy sweating with thirst, and a slightly restless hot feeling — drink the sour plum soup and turn the liquid into body fluids; the body returns to normal. Of course, yin-deficient people can also drink mai dong (ophiopogon) tea, or use a little sheng di (raw rehmannia) paired with yu zhu (Solomon’s seal) — these all nourish yin. Red tongue edges, scanty urine, yellow urine, heavy sweating, always feeling hot — these are the moments you need to nourish yin. When you sweat too much, jin ye (body fluids) are badly damaged, and yin-deficient people suffer especially.

In food, yin-deficient people also have rules:

💬 Note from Doctor Luo: People with stomach-yin or spleen-yin deficiency can eat a little lotus root, duck meat, and pork in summer — pork itself nourishes yin, but be careful not to pile on the seasonings; if you load it with Sichuan pepper and star anise, it’s no longer yin-nourishing. You can also eat water chestnut (ma ti), drink a little sugarcane juice (gan zhe zhi), and have a bit of watermelon to cool off — all of these are dietary ways of nourishing yin.

Closing: master the principles, and your spleen and stomach survive summer

The spleen and stomach are easily injured in summer, but once you master these principles, there’s actually a great deal you can do.

💬 Note from Doctor Luo: Strictly speaking, there’s a lot we can do to protect the spleen and stomach. Summer injures them easily, but if we grasp these protective principles, I believe everyone can come up with many methods — and dodge many dangers that might otherwise occur. Dear friends, that’s all for today. Thank you very much for listening. Next time we’ll discuss more Chinese medicine wisdom. Until then, goodbye.

What to take away

Feeling sleepy and losing your appetite in summer is a normal physiological adjustment, not a disease. Blood redistributes when it’s hot — the head and the digestive system get a little less, so you doze off and eat less. Even cats, dogs and monkeys nap at noon; even Singapore runs its air conditioning at 18°C because Lee Kuan Yew knew hot people get sluggish.
Principle one: eat light. No braised ribs or red-cooked pork in summer — the calories have nowhere to go. Eat slightly less; favor noodles, cold noodles, congee, mung-bean congee and lotus-leaf congee.
Principle two: never crave cold. In summer yang qi is outside and yin qi is inside — the core is already cool, so ice is the easiest way to injure the body (the Song emperor’s ice-induced vomiting and diarrhea; half a chilled watermelon before bed; legs soaked in ice water; sleeping belly-up with the window open). Room-temperature or warm is the baseline; ice is not negotiable.
Principle three: watch dampness. External dampness (sauna days, late summer) plus internal dampness (gulping water, iced drinks, sweet sodas that never quench) flood the spleen earth and kill the appetite. This is also why cholera and intestinal infections spread in summer — diluted stomach acid and a weakened spleen-stomach system let pathogens in.
Step one of regulation: tonify the spleen and qi. Whole grains, Huai yam and lotus seeds in congee; American ginseng for qi-deficient people, since summer heat drains qi.
Step two: resolve dampness. A thick tongue coating means dampness. Lotus-leaf congee (the leaf that Zhang Yuansu wrapped around rice for Zhi Zhu Wan, which Li Dongyuan finally understood at the end of his life), coix-seed and adzuki-bean congee, and fragrant kitchen spices like bai dou kou and cao dou kou — the “wind herbs” that rouse spleen-stomach yang.
Step three: nourish yin. Yin-deficient people feel their stomach burning and can’t quench thirst no matter how much they drink — the body can’t turn water into body fluids. Use suan gan hua yin (sour-sweet yin transformation): sour plum soup with wu mei, chen pi, shan zha and rock sugar. Signals: scanty dark urine, heavy sweat, restless heat, red tongue edges. Foods: lotus root, duck, pork with few seasonings, water chestnut, sugarcane juice, a little watermelon.
Master these principles and summer won’t injure your spleen and stomach — and you’ll dodge a great deal of danger along the way.

Compiled from Doctor Luo Dalun’s lecture series on the spleen-stomach theory (summer health edition). Original material from Doctor Luo Dalun’s lecture transcripts.